TT - this is a guess (as I don't have that combination).
The air keel is very light, which is in its favour and its not a bad hull shape either if you get enough air into it. Plus the 2-stroke isnt likely to weigh anything like as much as a four.
Hence I would be prepared to make a small wager that it will plane. At what speed I have no idea!
But there is no doubt at all that it will plane better with a 15hp!!