OK, I did some playing around to find out how to do this.

Charlie may have a better answer, but in the meantime:

I do think you need to create a count-in and click-track, but I think you may need only one assuming you need only 3/4 and 4/4 time, as BiaB will automatically choose the right clicks out of the track to match the time signature and will automatically set the tempo. Doing that does mean you'll need to allow the usual two-bars at the start of every song so your count-in will play, and you'll need to turn off BiaB's count-in.

Drums default to stereo, but in the notation window toolbar there is a checkbox "Mono", which does what it says. Check it and the drum track is now mono.

You'll set up a utility track with the count-in/click stuff and pan that track hard one side, and you'll pan every other track hard the other side. BiaB should then render as Charlie showed.

There are several ways one could create the click track(s).
I think I would probably do it with a custom style that I would just set on that utility track, partly to get the count-in style I'd like, but there are a number of standard tracks that may suit just as they are. There are several advantages of making one's own style for this and it's fairly straightforward. Where you may want more than one is if you want your click track to have swing.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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