Some historical clothing enthusiasts who AREN'T White because I'm sick of seeing White girls in 19th century clothes:
SewRena: specializes in 1950s American sewing & clothing, she is Black
Cosplay Queen: Chinese youtuber who does stuff like makeup, Hanfu of various time periods, Chinese classical dance, & cosplay. Also does a lot of Mukbang vids
MochiHanfu: another Chinese youtuber who specializes in Hanfu
NamiSparrow: Indian cosplayer who has some vids up about historic Indian fashion & sewing
Notyourmommashistory: Black reenactor who does vids on 1800s fashion, slavery in the 1800s, racism, vintage clothing, & also some cool video essays.
Cheon-Sik Yang: he is a Korean tailor who talks about Hanbok & traditional Korean clothing
Fashion & Culture with Kingsley: focuses a bit more on contemporary African clothing & fashions & geared towards fashion designers, but inspired by traditional African designs (from different countries and cultures, such as Ghana, Ethiopia, & Senegal) and clothing & a bit of historic ones as well.
The Couture Courtesan: mixed race Asian reenactor and historical fashion enthusiast who talks about fashions of various time periods, as early as the Tudor era up to the 1910s.
Eccentrik: Jamaican youtuber with vids focusing on fashion, & in particular either vintage fashion (I believe 1940s-60s), pinup fashion & hair & makeup, or vintage inspired sewing
Ora Lin: a nonbinary tailor (who I believe is Asian), they make videos about sewing & historical fashion of different periods & places, including Regency England, Jin & Ming dynasty China, the Edwardian era, & more.
Honorable mention: Snappydragon not a person of color, but she is Jewish & focuses on European historical fashion & Jewish historical fashion (including time periods the Jewish population would not be considered "White")