Enneacraft LEON's effect to burn for 900 LP shouldnt trigger if its condition is met, but control is changed before the trigger can activate. It should follow the same rulings as the Kashtira cards do, which follows the rulings for Aromage Jasmine.

Currently, LEON will still activate if Player A uses Enlilgirsu effect to add a card to hand, then take control of Player B's LEON. LEON will then burn Player B for 900LP.

https://code.moenext.com/mycard/pre-release-database-cdb/-/blob/master/script/c100245020.lua

https://db.ygoresources.com/qa#23484