How do make a midair dive?

I’m trying to make a simple mid-air dive as if it was ripped from Mario 64 or Odessey.

I want to be able to:
Jump and then dive, and when I’m diving I can press the dive button again to break out of the dive
and when I hit a wall I get stunned and fall for a little bit.

I can do a little bit with launch character but there’s no delay to when the dive is being used, it’s not smooth and it feels more like an air dash instead of a dive. How would I go about this from scratch?

I went and broke out Mario Odyssey to make sure I was remembering correctly, and I’m not sure I fully understand what you’re going for. The air dive very much feels like a dash, and the launch into the dive is instant. If you’re looking for a small bit of animation to play before the dive, an Anim Notify is probably what you need, although a lot of Mario’s appeal is from how instant things feel.

And bumping into a wall is just checking the direction of the impulse (of On Component Hit event) compared to the direction you’re moving (so sliding against a wall doesn’t stop you in your tracks if you’re only slightly off-angle).