Clone spammers like SM Naruto ,it would be hard for Kakashi to Kamui snipe the original unless he sniped him before he creates his clones
FTG user with sufficient reaction like Tobirama ,he can react to Kamui and evade it with teleportation .
Speedsters like Ay,Kakashi can't handle his speed .
Amatrasu users ,Kakashi can snipe them just fine but he doesn't has a counter for their Amatarasu .
double ms kakashi is becomes invulnerable through kamui so he can attack and at the same time not be hit, ay would be wasting his time.
MS obito
I meant 1 MS Kakashi ,Ay and every one i mentioned gets horribly stomped if this is DMS Kakashi .
MS and Rinnegan Obito would probably end Kakashi without plot