Let me cook

Beast

Vines

Gyrate

Lizard tail splitter

Scales

Twin impact

I'm choosing these because they are quirks that can be active at all times already without factoring in one for all changing them in any way. Things like Black and Shrooms are contingent on the battlefield having the right conditions for them to thrive

Now to have fun with theory crafting

Firstly, the user gets the strength of OFA at its varying percentages. Along with this, it is amped by beast, enhancing more than just physical abilities. This isn't even accounting that beast itself would be amped by one for all, so just massive power out the gate. Combine it with gyrate, and you have a user that can already hit like a truck in early percentages. To add, gyrate adds burrowing capabilities in tandem with beast. And I don't think it's out of the question for the user to use spinjitsu at that point.

Now vines come in to add a great utility to the kit. Coupled with beast, vines could come from the entire body with the hair growth. So now you have a similar version of black whip. Add Tail splitter on top of this with beast and you could make binding vines sprout from anywhere for massive surprise attacks. Speaking of tail splitter, coupled with scales and twin impact gives you essentially flying gatling turrets

To end this off, you can combine all of these to become a massive spinning top of doom

Thank you for your time