Does pop-up good for conversion? One pop-up per session only. I don't want my visitors to get annoyed.
Yeah, definitely it can work.
One pop-per visit is enough. Don't extend the number of it greater than one. Otherwise it will look like spam.
Yes, it is good but it also depends upon the content or matter of the popup.
PoP up to website is good. No issue. And on per session, would not affect user coming to your website.