Tiferes Yisroel does NOT prohibit trimming payos in Makkos 3:5, but he does write there that one may remove his beard with cream l’chatchila.
Maharshal writes not to SHAVE the payos at all, even with a scissors. He makes no mention of trimming where the concern would not apply.
Mishna Berura writes ?? ??? ?? ?? ??????? they may not be REMOVED completely. He doesn’t say they may not be trimmed.