I've watched the first two so far. This is how I'd rate them in terms of family-friendliness (0 being not family-friendly at all, 10 being very family-friendly).
Death-chan
3.5
She dropped quite a few swears, and her rap was full of them.
I hope she becomes more accustomed to this whole streaming thing. She alluded to this herself, but it was pretty clear that she was trying to keep a 'cutesy' voice throughout the stream.
Also holy fuck this girl's transition sequence is so fucking loud, and she used it pretty often. RIP headphone users.
Chicken-chan
7
I heard some "shit"'s in there.
I'll probably watch Chicken-chan's Fall Guys stream, at least part of it. As a Fall Guys master myself, I like seeing others fail at enjoy it.
Overall I'm impressed so far. I'm sure these two will maintain sizeable fanbases and all that stuff.