ItsLife

The 'simulator' that's referred to in those comments is not something that Luiss is using.
The commenter is referring to how quickly Luiss is doing their training. The commenter is suggesting that Luiss is using an outside program to speed up his battles.
As using programs like this is illegal, I would expect that Luiss would have been banned if they did something like this. As they haven't been banned to my knowledge, they likely are just very fast.

I know it's probably cheeky to ask, but do you know what kind of simulator they are using?

There is no simulator.
I tried my best to explain in my previous post what the commenter that mentions a 'simulator' very likely means, and that Luiss is unlikely to be using any of that.