It's harder to do than you think. It's one of those "you can't really do this" tools. Each live room produces an infinite number of echoes and the software can only manage a few. The trick is to get the right ones.
The middle of our building is a long hallway and a really tall ceiling three stories up. Polished cement floors. I don't think anybody else noticed that it sounds remarkably like a cathedral.
Dominus vobiscum. Et cum spiritu tuo.
I so want one of our many guitar players to sit in a chair in the middle and play out there.
"DX Reverb Light" from AnwidaSoft is a "stereo reverb" in the sense that it mixes a wee bit of left with right and vice versa, (crossover), whether you like it or not. Whereas Gverb does not crossover. In a real reverberating room there would be crossover, so Gverb reverb not having crossover is not natural sounding, (but you could add crossover if you wanted).
Freeverb also has crossover whether you like it or not.