Nice interview with Fujifilm at CP+ from Amateur Photographer once you get past a couple warmup questions.
When asked about pass-through charging of the battery in the body of the X-T2, they got a bit of a cryptic answer:
It all comes down to the hardware structure. It’s difficult to incorporate, but it is possible.
I would have loved a follow up question, but it sounds like had the X-T2 and and grip been designed differently, it would have been possible, but it’s not with the current design. Bummer.
There’s also some idle chatter on how different f/2.0 and f/2.8 is on a lens at 200mm, but no official confirmation that the new Telephoto Prime will actually be 200mm, but signs are certainly pointing to somewhere around there.