Female Ben Tennyson x Male Reader:

In this story, you will have something known as the Pokematrix.

It's basically like the Omnitrix but with Pokemon, now at first you won't have access to Legendary or mythical Pokemon and you can access all Evolution forms of Pokemon, also you'll have access to Mega Forms and Gigantimax forms.

Now, I'm not sure how I'd fit Pokemon into the Ben 10 universe, but hopefully I'll find a way.
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