A self insert dies and gets reborn in Highschool dxd as a regular average human with no special talent, magical ability or sacred gear.
Realising the kind of world he's in he starts training from his younger years.
His only path to a free life without joining a evil organisation or becoming a slave is through Ki manipulation or touki and eventually senjutsu.
Ki in highschool dxd is attained through breaking ones limit continuously and going beyond.
Just when the mc gets some measure of success in his Ki manipulation he gets attacked for being in the wrong place at the wrong time and dies.
Only to be reincarnated in another universe that turns out to be a alternate Marvel universe.
His only cheat being his knowledge of training himself and regaining his Ki.
Not to be confused with chi from marvel.
He starts by acquiring information about the timeline and major events of the world.
His access of Touki gets him noticed by the sorcerers and he starts training in the mystic arts.
Though he has no talent for complex magical spells,
He's better than the average trainee in Enhancement and eldritch energyconstructs along with manipulation of sling ring portals.
He focuses on those three and starts training hard.
While also learning basic elementary spells and healing magics.
But just when he was seeing tangible proof of his advancements The Snap happens.
He gets bliped out and instead of going to the red soul space he's booted off to another universe entirely.
He wakes up to a completely different world with different history and geography.
He realises he has been booted of to The Dc Young Justice universe.
But this time not only does he retain his trained physic he also has access to his basic Touki and the magic he trained in Kamara Taj.
A self insert in DC with basic Touki manipulation from DxD And Enhancement magic, Eldritch energy construct creation, Basic elemental spells and healing from MARVEL.