Ben 10 Ultimate Alien and Transformers: Prime.
In this one, Jack finds the Omnitrix, after the summer camping with his mother, when she dies because of a villain and Jack moves in with his cousin Ben and goes on camping on summers with Ben, Gwen and Max. He makes a team with his cousins, Ben and Gwen and his best friend Kevin.
When he is 17, one year older than Ben and Gwen, after they deal with Vilgax in Alien Force by blowing him up along with the Omnitrix, Jack gets the Ultimatrix and goes on a trip on his motorcycle, he ends up in Jasper Nevada, the place he came from and he moves there for a time, makes new friends with Miko and Raf and they meet the Autobots.
This is also placed after the events of Transformers Prime, where Optimus sacrifices himself for his planet after defeating Unicron.
Now then, let`s start this. It`s going to be hard for me, mixing two things, I just started writing fanfictions and it`s hard enough with both of them.
Now, please tell me who do you want me to make Jack date.
-Miko from TFP
-Kai from Ben 10
I will add more as it goes on.