Well it doesn’t seem to me like any particularly complicated tricks or anything are used in these. By looking at them it appears to all be based around shape and structure. It reminds me of something Disney a bit but I don’t remember what disney thing exactly. That aside.

If you wanted to replicate or try a style like this, I’d say look at these pictures very closely, then look at the way these characters normally look. Star at both for a while, then try tracing over one of his to get a sense of whats done with the shape or maybe more than one. Then look over again and think about what you did. Then take a new character all together and try to replicate the same concepts.

Well that’s my incredibly unprofessional advice anyway. I don’t even take art classes.