I've been around a couple of websites and forums all over the internet, and I've come to realize that many people experience different glitches/problems presented by Sheva's A.I.
I, myself have found it to be impossible to beat the final boss via weapons.
I have to kill it with the "Knife Scene".
Some people claim to have heard Shaman in the Wesker fight, and others have said they can't pull themselves up as Sheva.
I've experienced the BGM completely stopping.
Sheva's A.I. depends on how you equip her and what your command is.
Allot of people say they didn't have much of any problem with Sheva's A.I., but I've heard way more say that they did.
If you got anything specific to ask, go ahead.
And don't worry about the comments on thread bumping. It has some logic to it.
If a thread is too old you know the wrap, but some people just wanna desperately be moderators.

I call it being thirsty.
Just dust it of and be cool, broham.