Pokemon Champions director Kazumasa Iwao says that the mainline Pokemon games could gradually move away from turn-based battles, as Champions is available for fans of the current combat system. Pokemon has a vibrant competitive scene, and having a battle-focused game allows Game Freak to experiment with different types of combat for the mainline games like Winds and Waves.
The Pokemon series has a large number of different battle systems from PokePark to Conquest, but the mainline series has stayed mostly the same, with each new generation making changes and building on existing mechanics. Both Pokemon Legends: Arceus and Pokemon Legends: Z-A had entirely new battle formats, but these are the exception rather than the rule.