You use “chords” with midi drums & bass tracks?
I may not be understanding your question, but I thought you were initially asking if you can ‘import several midi tracks at once’ …if so, you can. I’ve done this with entire midi song arrangements I got from a bunch of midi song hit titles I have. In my experience, some of the song titles of older hits I’ve collected won’t import at all because (I assume) they were created in a non standard, non compatible midi format…probably created in an ‘Apple’ or ‘i’ product Most titles I have import fine though. Occasionally I’ll recreate an old song that I wanted to cover just for my own personal enjoyment, and will use pre-made midi songs for my ‘song starter’…that is if I don’t recreate in midi from scratch…which is actually better. Those pre-made songs often are machine gun-ish & cell phoney!
I don’t recall ever importing any of my own midi tracks I’ve done from another project I had created before…? Though I have imported midi loops I’ve collected from various sources, whether individual midi drum loops, bass/keys loops etc, or from construction loop sets, but in these cases, only importing one midi track at a time.
That’s all I have… if I’ve even understood the question.