Ahh, the teenage dog stage, always loads of fun! Thank goodness it does not last for 8 years like it does with us humans.
To harness the prey drive maybe make a flirt pole with a real skin on it and some sort of animal scent like they use to attract animals during hunting season.
Teach release cues, like drop it, or bring it back to you. It'll work both his mind and body. I will say that if you are going to use him for herding it might not be something you should use since it involves chasing and catching, not moving livestock in the direction you want them to go and may teach him to cause chaos when turned loose on sheep.
If you're just teaching him to not jump up on you, and don't want him to hold a sit position, maybe dropping the reward, rather then handing it to him, would work better. If you want him to hold the position then you are going to have to teach him that jumping up not only does not get him the treat but also causes the human to completely ignore him and if necessary leave him alone for a few minutes. Sort, he sits like you ask, so you click then as you give him the treat he jumps up to snatch it. First I'd keep the treat in my fist so he has no target to snatch at, and if necessary I'd have on a chainmail glove like this https://www.amazon.com/dp/B00W5DMX3C
so that if he grabbed at my fist it'd get him nothing. If I got down to him and he was still sitting open fist and give treat, if he snatches close fist till he settles, then try again. If he jumps up stand straight and ignore him till he sits then try clicking and treating again. If he keeps jumping go away from him and leave him alone for a couple minutes. He needs to learn that the consequence of jumping causes the things he wants to go away, and that 4 on floor is the best thing ever, treats, attention, play, walks, etc only happen when he is not jumping on his human. That type of training may take awhile but it does work.
Shadow my terrier mix had decided that my cousin David should not come over, he wasn't afraid of him just took a dislike to him, and every time he did Shadow would start growling, and hard staring. I'd tell Shadow enough and he'd keep it up so I'd pick him up and put him outside till David left. Shadow's goal in life was to be inside. There came a day when David came over and Shadow started growling then stopped, looked at me, looked at David, laid down and just kept an eye on things, he got to stay inside and was content LOL.