Here are two of the same Zimbabwe notes that are different sizes. I believe the larger one is the "correct"/more common size. So I guess the smaller note is the "questionable" one here. The smaller one was from a bundle of all similarly sized smaller notes.
Here's a high res scan of the two notes next to each other, black lines drawn by me to emphasize size difference:
(note that while misalignment and mis-cut corners, etc in these notes are pretty common, mis-sized notes are less common though this is not the first time i've ran into them.)
While all the minute elaborate details of both the notes are basically identical, the black ink on the bottom smaller note is noticeably lighter, and the color seems off in a few places (my extreme colorblindness is hurting my ability to analyze this).
Both notes hare small randomly distributed uv threads and specks that are visible under blacklight. The smaller note has noticeably less, but it's not necessarily an alarmingly small amount and might just be due to random variance.
How confident should I be that both notes are genuine?