Ehh, I dunno, we'll see, I guess. I think my big issue with the 3H team developing the next game again (besides the info from Emily of this game seemingly being developed at IS) is that it would be a pretty quick turnaround, especially if we assume it's gonna be more ambitious and higher budget, and especially given the fact that KT (albeit technically a different team) was also busy developing a seemingly huge and ambitious Warriors spinoff based on 3H. Then you get to the info on how this game is complete or almost complete (which has been said since at least February) and the fact 3H itself was delayed twice, and it just seems a bit too quick imo.
In addition, iirc Emily also said back in February that this game had been in development at IS for over three years, which would not only place the beginning of its development at minimum five months before 3H released (and since it was delayed from Spring to July, I assume KT wasn't finished with its development yet?), but imo make a lot more sense than another 3H situation as to how mainline FE had a relatively quick turnaround despite 3H's delays, HD development time, Three Hopes being a thing, and potential Covid delays. And if we assume that the remake is coming at least one year after the new game, then IS may have just started development on it later, after they had already spent a lot of time on the new game's development.
This June Direct had better reveal the next FE or I'm gonna lose it lol