TrioWorks

Nope, it was a scam indeed, you were right all along. I found those reddit posts: 
And also this: https://brightsanddesigns.com/web-designer-scam/
It is still a bit strange though. I mean why using a check for scamming people? My country doesn't even have that as an option so it'd be literally impossible for them to pay me that way. It may also be about personal data, I mean he was really pushy about giving him my address and name.
Anyway I owe you a big Thank You fisicx, cause I'd probably at least send them my personal info and maybe even fall for the whole thing if it wasn't for you pointing out the red flags.