Jumping into trees is already possible. Jumping from tree to tree would just be a matter of landing on the right branch...which is probably not going to be easy at first. In the manga/anime they never miss a jump but that's not realistic. It's not like there's going to be a tree highway to run along if that's what you're hoping for. You will be able to run on walls and water though and you'll be able to control your jumps with chakra (chakra-infused movements) so really the sky is the limit if you're good enough (pun only half intended).
Movement controls are still being debated and will likely be redone a a few more times before release. It's definitely not going to be simple though. You have regular movement, dynamic speed control, aiming mode, weapon mode (kenjutsu and others), ninjutsu mode, etc...
Nothing is finite yet but expect there to be a huge amount of control given to the players letting you guys do a lot of cool stuff.
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