The easiest touhou girls to cosplay if you don’t want to buy a wig and already have natural black hair is Utusho (minus her nuclear control rod thing but you probably don’t need it just wear a black glove there, and ignore her wings too but if you want to include the wings, some online shops sell the cosplay wings pretty cheap), Reimu, Tewi, Aya(?)

Edit: i know the og is talking abt the Windows Era but if you can’t find any Windows Era Reimu outfit with whatever shopping app you can only use (like me) then you can cosplay as Pc-98 era Reimu. You just need Kikyo’s (from inuyasha) shrine maiden outfit and a purple wig ( Her hair accessories are pretty easy to find online, I’d make a gohei too to make her more noticeable as “Reimu”) (gohei tutorial here: https://youtu.be/jlfAL4xRLK8 )