Two different teams, both forks of the original Popcorn Time project. As far as I remember, the team with the .io domain may have one or more members of the original project. I have seen on their sub-reddit, they do have an air of arrogance and spread a lot of a FUD around the team with the .se domain.

No, these groups had a significant war of words, especially when the build source for the binaries at the site you link was unavailable for some time. It was suggested that this late-comer was dangerous, but there are no other specifics for these claims of malicious intent that I've seen.

If you look again you'll find on reddit quite a few posts about malware regarding them.

Do you have an official blog post and clarifying you don't own .se domain and that project is run by different people? If not, I think you should write one.