I don't know anything about Genm. I would appreciate it if you would comment accordingly.
Firstly, This battle is really bad for Aizen. Passive's are useless due to the opposing side's physiology.
So is Aizen illusion passive?
Aizen's Kyoka Suigetsu is thought-based activated and works sight-based.
What's his answer to open timestop?
Time Stop is a Kido spell in Bleach. Aizen's Passive Powernull can handle this, but I'm not sure if it will work here.
I guess Aizen's Mid Godly Regeneration doesn't work here.
But Aizen's Reactive Evolution is very advanced. Reactive Evolution gives Aizen new abilities and resistances.
If KS requires the opponents to have 6 senses then Aizen cant affect Gemn because of his
Humagear Physiology
Aizen's Kyoka Suigetsu goes far beyond that in the High 4C key.
TYBW Aizen's Kyoka Suigetsu is 4D (Multiversal+).
Aizen can affecting /changing Infinite Timelines created by Infinite Possibilities.
Why wouldn't a skill that affects Higher Dimensional Structures (Timelines) work here?
Also, Genm's range is pretty bad. Aizen can even sense events of different dimensions.
Since it's SBA (4 Kilometers Distance), Aizen can feel Genm and He uses Hado 90 with a range of thousands of kilometers
[Sealing, Gravity Manipulation, Weapon Creation, Deconstruction and Space-Time Manipulation (Atomic)]
What can Genm do if he uses it?
(Kyoka Suigetsu and Hado 90 are Aizen's starting moves.)
Finally, Aizen Sosuke is an Extraordinary Genius. Just by looking, he can understand (Information Analyze) the abilities of his opponents and use a variety of abilities to neutralize them.(Like a Pocket Reality Manipulation and Dimensional Sealing).