There is a widespread minhag not to take haircuts during Sefira, in a way to mourn the students of Rabbi Akiva who died.
Would I be allowed to give another Jew (who didn't have the minhag or is ignoring it) a haircut when I myself follow this minhag?
Some say at the time which you hold of sefira one may not give haircuts to others who do not refrain from certain activities in that time (Piskei Shmuos page 60, Doleh U’mashka page 193). Others are lenient if the haircutter does not hold of the sefira during the time that he giving a haircut to someone who does, but one should initially not do this (Harav Shlomo Zalman Aurbach zt”l quoted in Halichos Shlomo Moadim 2:page 267:footnote 35)
