The Mishna Berura (531-21) paskens that one may trim his moustache, even areas that do not interfere with eating, on chol hamoed.
- Is there a problem due to sefira restrictions chol hamoed Pesach, or are sefira restrictions lifted during chol hamoed just as music is permitted?
- Are nose hairs the same as a moustache?
- What you are writing is correct, the sefira part would opnly atart after Pesach (see Rema 493-3). However it can only be done if there is a tzorech hamoed, otherwise it would be melacha on chol hamoed.
- Plucking hairs is not considered a haircut on chol hamoed, and would have the same halachos as a moustache.
- Gut Moed