Ketsuryugan genjutsu follows the same rules as other dojutsu genjutsu, that is, it's ineffective against other dojutsu.
LMAO, whut? The Susano can get severed by swords now?
The Ketsuryugan's dragon can't even be used unless you're in hell-valley or whatever that place is called. It's the only area that has water with enough iron content to be controlled. By default, it can only be used in that area, or another area like that.
Other than being controlled through the dojutsu...its just a water dragon jutsu.
It literally does the exact same thing as Sharingan genjutsu except it's never been shown to be OP enough to control a Biju.
Also, the second technique doesn't exist within AU. Chino created that technique herself based on the Spores made by White Zetsu, but since the white zetsu part of the plot has been eliminated from this AU, it also means China has no way to study the spores and hence no way to create that jutsu.
In most situations the Ketsuryugan is basically...base Sharingan without the eye of insight, it's the most underwhelming dojutsu in the entire series as it's just an inferior Sharingan.
The only real edge it has its the ability to control iron rich liquids such as blood, but clearly it's capacity to do that is rather limited and it can't one shot people by controlling their blood.