Its made for full body shots with one person. If there's multiple faces results will not be good. Also it will not work with portraits (face closeup) - will rather degrade quality.
Used models (just because those are fast):
You can download face segmentation from comfy model manager and face restore models from https://huggingface.co/datasets/Gourieff/ReActor/tree/main/models/facerestore_models
Decrease SEGM Detector "threshold" to value like 0.2 if face is not detected.
Takes about 7s to execute on 4090
There's bunch of custom nodes, but those are quite fundamental and comfy should have no problem downloading those.