Hey guys, use the best of your imagination? How do you think Digimon will cross paths with Pokémon? :D
My idea:
Team Rocket has been so evil and has a top secret project making a portal that can improve Pokémon and make them more powerful, but for some unknown mistakes, the portal ended up being a dimension connecting to another world where then Tai found it in someway and got inside along with Agumon, then Team Rocket found him and the mysterious creature. They thought it was a success and the Digimon was a great tool against Pokémon. And so, they used Agumon and confused his mind by technologies and prisoned Tai then a battle begins.