Video develop from top to bottom

Hello! I'm trying to make a video develop from top to bottom (as shown in the attached image)!
Can anyone give me a way to do it?

(Consider that I'm a beginner. I tried to find tutorials on YouTube, but the search has been fruitless, only showing me how to transform a video from horizontal to vertical and that's not what I'm looking to do.)

I would suggest you think about the "look" of a photo developing.

Perhaps it is quite dark at the beginning.

Perhaps the color comes in slowly, starting more black and white.

I would then make 3 versions of my shot.
1: a dark version of my final shot,
2: a black and white version of my final shot,
3: a full color version of my final shot.

I would then do a soft edge wipe from top to bottom, wiping from shot 1 to shot 2. Maybe turn this into a compound clip and call it "Wipe 1"

I would then do a soft wipe, with a later start time from shot 2 to shot 3, again put into a compound clip and call it "wipe 2"

I would then probably do a soft wipe from "wipe 1" to "wipe 2"

Maybe a soft edge power window with alpha would be a better tool to do the wipe?

At some point your initial idea will probably have to pivot, but that is where i would start.

I would suggest doing this in Fusion, with polygon masks as wipes, but as you are new, i'm guessing fusion is too much at this point.

If you are a new user, you probably have some reading to do.