But why change the AOA at all ?
That is the very beauty of a hydrofoil - it works so great, easy and performant with a fixed AOA for both low speeds and high speeds and maneuvers, with only subtle rider input to change between these, instead of any moving parts
If you had more negative AOA on stabilizer for takeoff, you would actually need a tad more lift/speed to takeoff - so not really desired.
And reverse, if you had higher AOA on stabilizer for takeoff so slightly lower takeoff speed, you would have to step back a lot, to push the foil up, and it would be more difficult to control
PF