As in DEEN's adaptions? Doubt it, especially since it's very likely they plan on retelling it. If you're talking about Fate/Zero, I wonder about that too. Depends on how the studio handles it if you ask me. If the studio decides to adapt all three routes (different versions on how the story turns out) then I'd go right ahead without worries. If they go with one story route then they might make it assuming you've already watched the prequel Fate/Zero for anime-viewers. Some people tell me that watching Fate/Zero first is like watching all the Star Wars movies in chronological order, some plot twists they might throw at you won't be too surprising since you already know how it turned out, like Darth Vader turning out to be Luke's dad. It wouldn't really bother me personally too much but I guess it depends on you.
HOOLLLLYYY SHHIIIIT. Old Joseph? I imagine it'll be a similar affair to the Dreamcast game in terms of fighting styles for him and young Joseph. And Lisa Lisa being in it is cool, they are still missing Stroheim which annoys me haha. I'm amazed at the lack of characters from 6/7...only having Jo2uke for Jojolion makes sense currently due to the lack of characters....but they will be to come I imagine.