OK If you google this you find a lot of stories like this https://metro.co.uk/2019/08/19/man-seriously-burns-his-balls-afte etc ...
However I did try it last week and this is my story
I went to a salon to get what was advertised as a shave but was indeed cream based hair removal. Its was put on my abdomen testicles and penis. It was on about 4 minutes before been washed off. I had no issues at this stage and was very happy. Said thank you and I will be back again.
About an hour later I did notice some swelling on my right testicle and it was sore. No terrible pain or anything and not burning About a 3 on a 1-10 scale.
That night I did sleep on my back.
The following day the swelling was down but it was still red and sore. But this went a way through out the day and the following day it was fine.
I dont know if this swelling was caused by the cream or just a reaction to getting the hair removed. It was only on one small part of my right testicle.
I did also get some red bumps on my inner leg but this was regular shaving bumps and not sore or anything
over all it went well and I was happy with the experience. I dont know if I would risk it again though. I may use a cream to remove the hair from my bellybutton down but dont know about putting it on testicles
I think they used Nair All hair removal but not certain.
It seems very difficult to get real reviews or information on this. Its either horror stories like above or affiliate sites selling stuff but anyhow that's my experience