POLES.

I have a horse that does exactly what yours does.

If your horse has a bigger stride, I put a pole nine feet infront of the fence and nine feet after. It's 'giving them lines to color between'. The poles slow them down.

If that doesn't work for him, try three or four poles infront of the fence and one, after.

Beyond that, gymnastics are your best bet. Bounces, or, a fence, a placing pole nine feet after, and then another fence (and then another pole after).

Don't give her a long approach. To keep her settled, don't give her time to think about it.

Another idea is to set up three or four fences in the arena and keep changing directions when you land, keep her guessing. Don't approach from the same place, just keep changing it up.

“There's a lot about discovering who you are and how difficult that is, and it never stops.”
- Libba Bray