If you use a DAW it is easy to make 5/4 in most styles. I've never made a whole 5/4 song in BIAB (like "Take Five" or "Mission Impossible" Theme) but I sometimes add a beat or two to a bar in a few places, making an occasional 5/4 or 6/4 bar and it was never any problem stealing a beat from BIAB tracks and adding them to the bar. You just have to decide where the secondary stress should be (2+3 or 3+2) and put a stress or downbeat on either the 3rd or 4th beat of the modified bar. A 3/4 style becomes 5/4 by deleting every second 3rd beat to get a 3+2 "Take Five" feel. Adding a beat to end of a 4/4 style bar (copy ether the 2nd or 4th) will make a convincing 5/4 with a 2+3 stress.

Of course, this means you have to use a DAW and cut and paste the tracks from BIAB to the DAW before rendering, as BIAB cannot directly play these (it is not a DAW!)

Sometimes cutting and adding a beat will make a particular instrument sound unnatural and you may have to choose a beat from another location. Even easier, if you can afford it, is to have the Melodyne plugin in your DAW and just smooth out or change the notes in that one spot to make it natural.

Cutting or adding beats from a single style will always sound better than using two different BIAB styles because the instrumentation and sounds may not exactly match.

If you plan to use a DAW to make a continuous 5/4 song, I suggest using a DAW that has ripple-delete (or "ripple-edit) which means you can delete or add a beat and it automatically moves the rest of the track to match the cut (instead of having to drag the rest of the track backwards or forwards. I understand Reaper and Studio One do this quite well, and Cubase can do it but not as easily.