It looks pretty weird, having both of them open, i believe it would be better to have something else

This could be Achieved by comparing the local version to a version stored on a server f.e. in the json format and if the server version is newer, it could automatically download and install the new update.
Squirrel should be able to help you with installing.
I can provide logical support, as i already coded multiple updaters in js, but im not good in c#, so i can't help you coding it

国服是 YuanShen.exe
国际服是 GenshinImpact.exe

You could implement this using the small image and for hover text the level
Every Char could have a Different Image, which represents the character, just as FF XIV is doing it