Hi KF2
I get that you're looking for insights from other users' workflows. Right now, there isn't a report that can make this process easier, but the supplier transaction report is the closest we have to help identify your supplier transactions.
Regarding your other question, there's currently no feature to automatically check invoice numbers against entered purchases. I can see how that would be super useful for mass transaction statements, though. I'd suggest posting this on the Ideas Exchange board for future update consideration.
Hopefully, another user will share their workflow and help you out.
THanks,
Genreve