Page 1020 of the manual shows a pretty good way - "Exporting Individual or Multiple Tracks as Audio Files". It looks like this will bounce each track simultaneously to a new audio file.
Or you could keep it in-house (and simple) and bounce each track to a new audio track one by one - it'll take a bit longer though.
You can even go as far as avoiding bouncing altogether, by just recording each midi track to a new audio track in real time.
I remember Mojave having a pretty good method that made sure each new audio file ended up being the same length, I just can't find it at the moment. I'll keep looking though, I know its in here somewhere!
Hope that helps