I just did that check too, I removed translation from both levels (it was tra...

I just did that check too, I removed translation from both levels (it was translatable in second level previously) and still issue existed

Config:

Node (translation enabled):
--Paragraph A (field not translatable)
----Paragraph AB (field in A, field translatable before, not in the last test)
------Image field (inside field Paragraph AB, field translatable)

On my fresh tests, I was able to get translation working even after setting translatable setting to false in Paragraph AB with new content but still the issue exists :(