MS Obito decimates kakashi
Obito can cancel kakashi's kamui, thus negating his chances of sending a clone to the dimension.
Should kakashi actually manage to send a clone to the dimension, obito can then warp there & use a large scale katon to take care of the clone from a distance. Kakashi warping a clone to the dimension is impossible in front of obito, therefore his intangibility is still in effect for the fight.
Due to kamui, obito has superior ninjutsu, & mokuton can still drain kakashi's chakra should he manage to get trapped by it [he doesnt have the physical strength in order to escape, so it's still effective]. Obito's katon is also overwhelming compared to anything kakashi has shown us, & his healing ability/stamina are much higher than kakashi's as well.
Due to kamui, obito also has superior taijutsu/kenjutsu/shurikenjutsu. His skill when handling shuriken & madara's gumbai surpassed kakashi's skill with shuriken when kamui becomes a factor.
Not even going to mention izanagi or summons...
& If this is rinnegan obito, then it becomes even worse due to black rods & the gedo mazou.