There's a Moldovan guy (I assumed he was romanian at first) who has similar style (wears long skirts, makeup, keeps his hair long) and documents his life on Instagram, I forgot the name of the account. It's obviously technically not the balkans, as from what I remember he lives in Chisinau, but he usually either gets compliments from more open minded strangers, or random insults or questions "why do you dress like this?" and people that bother him. I feel like if you also look up on social media similar accounts of Balkaners who have similar style documenting stranger interactions or reactions, you'd get a better feeling of what you might experience. For Bucharest, for instance, I believe you'd be mostly fine, in particular in the tourist/central areas. I can think of a few people more famous in social media that dress out of social norms, so it's not like it would be a big shock for the locals. You might get a judgmental look or two tho especially from older people - keep in mind they did have a whole group of Christians throwing holy water etc after a pride parade event. So perhaps stay in more tourist areas, if you feel unsafe just tone down the look, and maybe travel with a friend group.