As many know, Disney struck all legends content from the Star Wars canon when it purchased the franchise and has since slowly drip fed material back into canon. One example of this would be how Grand Admiral Thrawn was brought back into the fold via Star Wars Rebels, but since games published since the acquisition are canon too, they are perhaps the easiest way to re-canonize material. And for Star Wars Jedi: Fallen Order, there's a ton of things that could be brought back into the fold.
However, there's always been sort of one grey area. The older Kotor games are set so far in the past that, technically, nothing violated canon, but Disney has never came forth and declared them canon neither. In particular, Darth Revan's canonicity has only been flirted with by Disney, with the most just being an acknowledgement of the name. Star Wars Jedi: Fallen Order 2 could easily fix this.
Disney Star Wars Canon - Darth Revan
Darth Revan, the Jedi-turned-Sith-Lord-potentially-turned-Jedi, was the main character of the original Kotor, and many would like to see him officially and formally canonized. Instead, the most that he's been given is a mention in the Star Wars: The Rise of Skywalker Visual Dictionary. Sith troopers were named after ancient Sith Lords, with the Revan Legion being activated in 35 ABY as part of the Final Order.
However, that's hardly meaty. Using Darth Revan's name is a simple acknowledgement, with Disney mostly just toying with the character. There's been nothing to officially canonize the events of the games, and while this could be extrapolated to mean so, it simple doesn't give the fan-favorite character the justice they deserve.
Jedi: Fallen Order 2 Fully Canonizing Darth Revan
The most solid way to actually do so would likely be through Star Wars Jedi: Fallen Order 2. In it, not only are the events considered canonical, but so far it has been so self-contained as to not stumble over the likes of the various film trilogies, nor the Star Wars animated series. As such, Jedi: Fallen Order 2 (if following in this path) would have the freedom to directly reference and address past events, not unlike when Ezra Bridger discovered a crossguard lightsaber.
While more than the name is really needed, it wouldn't take much for Jedi: Fallen Order 2 to establish Raven as canon. Perhaps Cal Kestis ends up in an old Sith temple where the history of the old Sith Wars is explored, talking about how Revan was corrupted but redeemed. Perhaps there's a simple discussion with Cere about the history of the Order pre-dating the current Republic. At most, maybe there's a quest where a Revanite talks about the importance of the character and their actions.
Doing so would acknowledge the full character of Revan but also formally acknowledge and canonize the events of the Kotor game. After all, if EA is serious about single-player Star Wars games, Knights of the Old Republic 3 has to occasionally be brought to the table. But before making that leap, the first two games have to be formally canonized.
Star Wars Jedi: Fallen Order 2 is reportedly in development.