The legend himself is joining the hunt for monsters. If you boot up and see Ryu in your game – don’t panic! Capcom has a crossover that sees you play as Ryu in Monster Hunter: World.
— Monster Hunter (@monsterhunter) February 15, 2018
So long as you have Street Fighter V save data on your PlayStation, you can access Ryu. What you need to do is to go to the Gathering Hub, head over to the Arena Counter and accept the quest “Down the Dark, Muddy Path.” This is a Rank 3 hunt and sees you face off against a Barroth.
What are you waiting for?