"""""""""Well, since it seems that there's no G2 Fillets in any affordable software either, it's moot anyway. """"""""""""""

Well, MoI does G2 fillets. Also G3 fillets as well.

""""""""""It's really too bad that on these models, imported from Catia as Step, I can't even fillet a single trivial edge, no matter what mode in MoI."""""""

But why?

Can you produce "ANY" example that doesn't work, that is not under NDA? I mean, a "single trivial edge" is kindof a broad, general statement.