I had an idea recently: what if Serena had never met Ash in the Pokémon anime? Rather than Ash finding her and bandaging her up, someone else does. Years later, this young man comes to the Kalos region to help his uncle Professor Sycamore study Mega Evolution. When Serena comes to get her first Pokémon she recognizes him, and offers to travel with him.
Pretty straightforward. I will use my OC Rex Drake. If interested please send me a message. :)