I'm looking for a smaller than usual case that is capable of mounting an ATX motherboard and if possible a 280 AIO and has enough space for a 2080ti.
I just hope GPUs don't get any bigger...
How long is your GPU?
I don't know. Lets say, for arguments sake, 305mm.
The Raijintek Thetis is pretty small and can fit ATX motherboards and larger GPUs, if you are flexible with storage requirements and pick your PSU carefully.
Meshify C, one of the smaller mid tower cases out there.