DS1 is 13 and completely unco-ordinated. He is very bad at anything involving a ball.
Until recently it wasn't really a problem because he/we spend a lot of time outdoors and he would usually be running around like a made thing playing some made up game
However, now he's all grown up he's doing less and less of that and will sit outdoors with a book or walk with the adults (active but not making you puff exercise IYSWIM)
He sometimes comes to park run with me and is a reasonable runner but he doesn't enjoy it and comes under protest. He's a good swimmer but complains when I make him go. He does love going to Airsoft (grown men running around the woods with toy guns) with DH but they only go once a month. It's only on about once a month and in any case it's far too expensive to be doing much more often.
What do your young teens enjoy if they don't like sport?