I've been hooked on Genshin gameplay for the past month, and I'm glad it showed up as I wait for more stuff in Avengers. The funny thing is that Genshin share combat similarities with Avengers. I put hundreds of hours into both, and the main difference is Genshin has a big open world, and you don't play with the full party visible and active at the same time unless you're in co-op.
Similarities:
Characters may have a ranged attack aiming mode (not all have this in Genshin)
Elemental effect combos (Genshin is deeper in this, it's based all around it while it's not necessary but still a big part of Avengers)
Seamless switching between ranged and melee.
Minor ability/abilities and an ultra ability.
Traversal abilities.
I play on controller on PC with gyro and touch pad (Steam Controller). Genshin require me to emulate mouse look with analog settings, which is horrible, both for gyro and the touch pad. Avengers is a dream compared to Genshin controls and aiming, but Genshin's open world exploration and single character with swapping between them makes it all worth it.
Also Genshin loads super fast on the SSD, while Avengers take a long time. Avengers likely have a lot of load masking for console with it's talking between mission travel sequences, watching animations of the avengers waiting for the Jet to get to the destination, and stuff. I hope they take that out of the PC version if the new gen versions allow you to skip it since they don't have HDDs. I want faster loading, or the ability to disable the transitions!