Hi, thanks for playing and for letting me know about that void screen! (It's been so hard finding all the bugs and softlocks with how many seed combinations are possible! Thankfully that one is pretty minor and easy to fix!)
On the tech side of things, yes those 3 "loading screens" do in fact determine the seed so skipping past it will most certainly impact the seed results, I'd be careful with doing that.
The way it works is that Juni is shifted in an infinite loop between 3 different screens per each of the 3 loading screens
(screen 1 shifts between 1 2 3 )
(screen 2 shifts between 4 5 6 )
(screen 3 shifts between 7 8 9 )
On each shift one flag in that group is set true and the previous flag in that group is set false and since Juni's walk and jump animations are slightly random +humans are not 100% consistent with their inputs the timing at which they get through each screen if makes the flags semi-random (just enough to make this work).
This means once you exit the final "loading screen" you'll have 1 flag set at random from each of the 3 loading screens.
1,2,3
4,5,6
7,8,9
This will then display as the "seed" of your run. (the collection of 3 different flags) (27 unique combinations)
Then the way the world generates is that every screen will warp to 1 of 3-4 variations based on which flags are active.
Fox example:
screen 1 might warp based on flags 1,2,3
screen 2 might warp based on flags 4,5,6
screen 3 might warp based of flags 7,8,9
Therefore as a player walking through screen 1 into 2 into 3 it will always be a slightly different experience and always feel slightly different because each of the flags will likely be in a different order (although once you play it enough you'll start to quickly recognize certain layouts)