Is Deadpool connected in some ways to X-Men Origins: Wolverine and X-Men: Apocalypse?
Yes and no.
In Timeline Prime Alpha, Wade Winston Wilson was born in the ‘50s or so.
X-Men Origins: Wolverine is the depiction of the life of Wade Wilson without any mutant (Unknown or Wolverine) tempering with the past and thus changing the timeline.
In Timeline Prime A, Wade Wilson was originally member of Team X, the mutant squadron that William Stryker assembled for his personal agenda. James Logan quitted Team X in 1977, at the end of an important mission in Africa.
So it looks like Wade was recruited in 1971 or early 1972, and he was already an adult man by that point.
The vast majority of X-Men Origins is set in 1983: the events of the Weapon X Program (Wolverine) and the Weapon XI Program ("The Dead Pool"). Indeed, as stated on-screen, the programs were performed 6 years after Logan quitted Team X.
As we already know, the mutant Unknown changed the past in 1903 and, as result, some humans and mutants were born earlier or later in the new iteration of the timeline (Timeline Prime Beta).
The beginning of DOFP showed us that - by early 1973 - Logan was located in New York, working as bodyguard. At the same time, Stryker was testing some mutants in Vietnam (Havok, Toad).
Wade wasn’t even born (yet). According to the time Deadpool is set, we can assume Wade Wilson Version II was born in 1976. Same father, maybe different mother (a younger mother).
When 2023’s Wolverine started to operate in 1973, he essentially turned Timeline Prime Beta into Timeline Sigma (FC, DOFP, XM:A). So the timeline was altered for the second time.
In the new, definitive timeline (Timeline Sigma), Wade Winston Wilson is turned into Deadpool only in 2015.
In regards to the two Wades’ biological status.
Wade Wilson’s original powers in Timeline Prime Alpha: kinesthesia, superhuman agility and geometrical perception/precision.
Wade Wilson in Timeline Prime Beta/Sigma could be classified as "Latent Mutant" at the very beginning, and experimentation just brought its real nature and powers to the surface. Problem was that his mutant power went triggered seconds after oxygen deprivation had extensively ruined all cells of his body, and thus his regenerative factor "registered" his damaged appearance as his "default mode".
Is the Colossus in Deadpool the same of the OT?
Of course. In Timeline Sigma, his metallic form looks different because
In Timeline Prime, his parents were probably scared their son would be hunted, feared and shamed so they sent Piotr Nikolaievitch Rasputin to America either undercover, or directly to the X-Mansion to be safe. In Timeline Sigma, with the higher possibility of a new acceptance, Colossus’ parents would decide they probably won’t need to run away with/hide their child out of fear of being persecuted and take a chance and remain in Russia to raise him. The new environment he's in allows him to get bigger (different eating habbits, influenced to become a bodybuilder or something).
Colossus then decides to move to America out of his own free will very late in life (thus retaining the accent), and is picked up by Professor X while he's there.
Apparently, we have learn from Deadpool that Timeline Sigma Colossus needs to breath and eat even in his metallic form.
Is Origins consistent with X2?
In X-Men/X2 either Xavier and Stryker suggested that Wolverine’s mind has been wiped out 15 years before the events of the first two films (2004).
Xavier: “Logan, it's been almost fifteen years, hasn't it?”
Stryker: “How long has it been? Fifteen years? You haven't changed one bit”
We can assume Wolverine encountered Stryker again in 1989, and the Colonel tried to capture and/or brainwash Logan. Eventually, his memory is wiped out like before (using some method other than the adamantium bullet – see the alternative scene of X-Men Origins). That would also explain why Logan recovered the infamous jacket he left in Gambit’s plane, because this new scenario would start with Wolverine investigating his past and hunting down the mutant Cajun in order to find out the truth about the Three Miles Island events.
Gambit presumibly died during this second round with Stryker, because he didn’t reappear later in the timeline. Such a powerful mutant would have been eventually detected by Xavier and recruited as X-Man, so that would explain his absence in the OT.
Basically, there’s an imaginary prequel movie in-between X-Men Origins: Wolverine and X-Men, set in 1989. Sort of X-Men Origins: Wolverine 2.
Wolverine and Sabretooth
We learn in the intro that Creed and Logan share fathers and so are brothers or half-brothers. And for this reason they stick together for nearly a century. An odd couple where one is essentially good and the other evil. And yet as brothers they stick together and this unfortunately effects Logan in a bad way - that is until he frees himself and leaves for the Canadian woods... in many ways he was a captive until then.
However, the abusive father has an obvious physical resemblance to how Creed will later look (and not only physically). And the "adopted" gentleman father has a very obvious resemblance to Logan - both in his kindness and his physical look (it is quite amazing how they could find an actor looking so much like Jackman).
So why did the filmmakers do this, if the abusive father was the only father?
The answer is of course that they are in fact not brothers.
The abusive father had an affaire with Logan’s mother and for this reason the man arrogantly believed he was the father of this higher class kid. However we know now how Logan later got his real fathers looks, and so It must be untrue.
Creed and Logan’s relationship is a lie and their brotherhood is fake. They are opposite and ethically they are not bound to each other. This matters in many of their later battles. They are in fact enemies
Since Apocalypse establishes Ororo Munroe is 18/20 years old in 1983, we can finally claim that the deleted scene in X-Men Origins: Wolverine is not canon, because it showed Ororo as a 8/10 years old little girl in 1977 (when James Logan quitted Team X in Nigeria).
Actually, I would like to see that snippet re-inserted in X-Men Origins, because that’s the only flashback we got about Storm’s past in Timeline Prime Alpha. She looked like a poor and scared child wandering alone across the country, maybe stealing here and there (exactly like in the comics). Besides, having Storm on X-Men Origins would reinforce the notion the movie was about the origins of many main characters (Cyclops, Emma Frost, Gambit, Quicksilver, Banshee, Sabretooth, Stryker, Mastermind) and not just Wolverine.
The original Jean Grey of Timeline Prime Alpha was born in 1971. When she was discovered by Charlex Xavier via Cerebro, she was 14 years old (1985).
She may have used the codename "Marvel Girl" when the X-Men formed in 1990.
She died in 2005.
The new Jean Grey of Timeline Prime Beta/Sigma was born in 1965. She was the little red-haired girl watching above the skies in DOFP (1973).
We don’t know if the two Jean Greys are still the "same person" or two different persons coming from the same parents and the same genetic pool; since Famke Janssen played both (OT and DOFP), we can assume it’s the former one.
Angel/Archangel in Apocalypse
The Angel in X-Men: Apocalypse is the one and only Warren Kenneth Worthington III. Supposedly born in 1963.
We must assume that - in Timeline Prime Beta/Sigma – Warren Worthington II had a child when he was younger, earlier in the timeline.
In Timeline Prime Alpha, Warren Worthington II was older when he had a son. Likely, he married a different woman. Warren III developed mutant wings in 1995, as seen in the flashback sequence of The Last Stand.
So basically, the two Warrens are not the same person. Thery share the same father, even.
Jubilee in the OT is not the Jubilee in Apocalypse
The Jubilee in X-Men: Apocalypse, Jubilation Lee, is the real deal. I mean, it’s the Jubilee from the comic books. The Jubilee in the original trilogy (OT) must be a mutant kid bearing no relation to her.
Timeline Sigma Xavier absorbed the Timeline Prime memories from Wolverine (as seen in DOFP), so later in 1983 he just gave Jubilation Lee the Jubilee codename he had in his memories. Thus, it was the other way around: the 2004 Jubilee Prime indirectly inspired the 1983 Jubilee Sigma. End of the story.
In the cinematic universe, some physiological traits and powers keep emerging from time to time, it’s a recurring theme. No mutation is 100% unique in nature.
Their powers might be different anyway. Comic book Jubilee shoots fireworks out of her fingertips. But in a deleted scene featuring the Jubilee of the OT, we see her conducting electricity with her hands. That’s similar to the original Jubilee’s power, but it’s not the same.
The Psylocke in X-Men: The Last Stand was an asian girl with the Crimson Dawn mark on her eye and different mutant powers (shadow teleportation). She must be Kwannon. The Psylocke codename was only suggested on the final credits of The Last Stand anyway and you can ignore it just like you must ignore the timestamps of the same movie.
The Psylocke in XM:A is obviously a different girl with different powers.