Yes, a judge can preside over a hearing via video, and all parties can participate via video (this became common during the pandemic, and I've done this several times). This is particularly useful if it's going to be difficult to transport an inmate. Now, whether the public will be allowed to watch? That's up for debate, especially given the sealed records vs. the high public interest.
I think that logistically it may be hard for Carroll County to handle a hearing, particularly the one involving unsealing the records, where there will be large numbers of reporters, members of the public, ect. That courthouse simply won't have the staffing to provide security and likely won't have enough space. It certainly doesn't have enough staff based on what Judge Deiner reported (see the link earlier in the thread on his description of the court resources). I could see the Carroll County prosecutor and the defense attorney (once he/she has appeared) traveling to Ft. Wayne for a hearing like that. If the hearings remain "sealed" without reporters, then Carroll County could probably handle hearings.
The magnitude of this case due to international interest is not the norm here, and I think everyone's going to have to think about practicalities in deciding where the hearings take place. And that's assuming the venue isn't changed, but that'd be the first motion I'd file if I was RA's criminal defense attorney.