A: Yes, in v8.3 and later, you can enable multi-GPU via the Texcelle.ini file:
[GPU]
EnableMultiGPU=1
PrimaryGPU=0
SecondaryGPU=1
A: Yes, using VMware Horizon with vGPU (NVIDIA A16 or L40). Allocate at least 16 vCPUs, 64 GB RAM, and 24 GB vGPU memory per VM. Avoid VirtualBox. nedgraphics texcelle system requirements top
Even with top hardware, Texcelle needs configuration: A: Yes, in v8