If your talking about the 7min cutscene, that's going to be insanely hard to get Sunshine at least the leaderboard for it back when it was just the GCN version had an insanely long community vote about that I think it was 2017/2018. Anyway it was basically taking everyone that had ever submitted a run to the leaderboard level community vote. It was stupidly close but the decision was to keep the original time from file select.
Now mind you that there could be an argument since All-stars version is a different version and is part of a collection but I figured I'd at least provide some context.
Starting from peach file is used for racing though if you are talking about after the 7 min cutscene.
It may also be considered for category extensions if the mods decide to make their own leaderboard dedicated to 3D All-Stars
Peach File is when you start the game on the airstrip after the first two initial cutscenes (plane flight + FLUDD tutorial), but before the third initial cutscene (the Mario trial). It is currently an accepted timing method on the main SMS leaderboard. 2 minutes and 30 seconds are added to the timer at the beginning.
Everything is going to be up in the air for a while with this game so who knows how everything will shake out.
I think it would make sense to add it since it's allowed in the original and was always the least controversial option to skip the cutscenes anyway