As I am using EAD right now, and she is studying using her AOS (GC pending) status.
Do you think it is possible to let her come back to USA by B2 business status,
-I don't think she can get the B2 visa due to the immigration intent (same problem as the F1 visa application). You may try to get the H1 status and thus, she can apply for the H4 visa to come back.
and then transfer to F1?