What are the patterns in these two matrices?

I found these puzzles on https://iqmentor.io, and could not figure out the solutions to them. Any thoughts?

I also posted this on Reddit. Including the link here in case you'd like to see more people's attempts: https://www.reddit.com/r/cognitiveTesting/comments/11b8tiq/iqmentorio_what_are_the_patterns_in_these_3/
(In the Reddit post there was a third puzzle, which someone already posted a satisfactory solution to, so I did not include it here.)

1. This seems somewhat similar to another problem whose solution is described in this video, (and in this video with visuals).
My thoughts:

! Best I can come up with is that it's a topleft-botright diagonal sequence, with at most one of the corners moving sides across the horizontal bar, which would yield option 4 as the only answer, but that seems too weak of a pattern compared to the pattern of the puzzle in the video.
(Also, that pattern does not completely hold, because in cells 3-4-7, between 3-4 the white square moves to the top-left and is obscured by the black square, but then after the black square moves between 4-7, we should now see the white square in the top-left but we do not.)

2. This seems like it should be similar to problem #35 in this video.

After putting the below together I realized I made an error, which I retroactively highlighted below, but including it anyway in case it inspires any ideas.

* This article was originally published here