When Vincent Valentine was first introduced to Cloud and the party, his circumstances are quite odd compared to other character introductions in the game. When players discovered Vincent in the original Final Fantasy 7, he's spending his days in a very dark and strange corner of the world. The ensuing conversation is, well, confusing at best. While Vincent's background is genuinely interesting and should be integral to the story, his original introduction will likely be changed in Final Fantasy 7 Remake.
Vincent is one of two optional party members in the original game, though it's unclear if this will stay the same in Final Fantasy 7 Remake's second episode. Considering he's the only party member from the Final Fantasy 7 universe to get his own spin-off game, it's very possible he could become a far more integral part of Remake's narrative. Since there's already been several flashbacks to the years prior to the Nibelheim incident, Remake's second episode could potentially include and revamp Vincent's origins and introduction as well.
Vincent's Original Introduction in Final Fantasy 7
The initial introduction of Vincent in Final Fantasy 7 is a little strange. Even in a game with an animatronic Moogle and cat being controlled by Midgar's head of urban development, finding Vincent is comparatively just as odd. Spending his days as an apparent vampire, Cloud and the party discover Vincent sleeping in a coffin deep in the basement of Shinra Manor. Cloud wakes him up from the coffin and tells him about the current state of affairs with Sephiroth, and eventually Vincent returns to the coffin to "atone for his sins." Vincent eventually explains he's a former member of the Turks, and sheds some light on Sephiroth's origins.
Granted Vincent's backstory is fleshed out far more in-depth in Final Fantasy 7: Dirge of Cerberus, but without that context, there's only one flashback (also optional, and discovered in a different part of the world) that describes Vincent's origins as a Turk and his relationship with Lucrecia. While it was initially believed that Sephiroth was born strictly from Jenova cells, this flashback reveals Sephiroth was actually Lucrecia's son. Hojo, technically Sephiroth's birth father, eventually wounded and experimented on Vincent when he attempted to stop his experiments on Lucrecia's unborn son. It's vaguely inferred that Vincent's guilt and Hojo's experiments kept him in that coffin for years.
Modernizing Vincent's Introduction in Remake
That above description is being a bit generous, as the actual in-game cutscene is far more vague. Given the narrative content associated with Vincent's character, it would make sense for Vincent to be a far more prominent character in Final Fantasy 7 Remake's part two. There'd be presumably two approaches to modernizing his appearance in the second episode: Revamping his character introduction entirely, or adapting his introduction as faithfully as possible. It's hard to say which would be the more likely option, considering Final Fantasy 7 Remake was able to faithfully adapt Cloud's cross-dressing scene into the game to great acclaim.
Either way, there's a few surefire things that would likely change in Vincent's introduction and character. The main thing would be his position in Nibelheim manor, since in the original game he's found in a literal vampire's coffin. How this particular scene could be modernized in the slightly more serious tone of Final Fantasy 7 Remake is hard to envision, given how comically his coffin scene takes place in the original game. Final Fantasy 7 Remake has been able to surprise fans before, so it's possible the team could adapt this scene faithfully, but the scene will likely be reworked given the nature of Vincent's narrative importance.
Vincent's Importance In Final Fantasy 7's Story
Vincent's narrative importance will likely be far easier to implement in comparison. Given the context of Dirge of Cerberus, and the development team's desire to expand many pivotal characters in Final Fantasy 7 Remake, his origin story will likely be less vague. Vincent Valentine could potentially take on a more Sephiroth-like approach in Remake's second episode. Instead of being a mysterious and strange character found in a side-room, he could be more front and center for the events of Sephiroth's birth and the Nibelheim incident. Rather than just discovering his importance by chance, Vincent's conflict with Hojo and Lucrecia could be expanded further.
Of course, the Remake would need to retain Vincent's guilt and self-imposed isolation, as it's a critical part of his character development that wouldn't make sense to omit. Hojo's betrayal and experiments on him need to have weight on his character, and could help contextualize why he's sleeping in the basement of Shinra Manor for over two decades without aging. Emphasizing the effect of the experiments on his psyche and the progenitor of his guilt makes his character interesting, and should be expanded upon in Final Fantasy 7 Remake. Of course it could potentially reduce his ability to be an optional party member like in the original, but who wouldn't recruit him anyway?
Final Fantasy 7 Remake Part Two is in development.