I'm going to shill two good South Slav-related ones on /his/ (no English subtitles though)
https://www.youtube.com/@veritasomniavincit2070/videos
First one is run by Croatian crypto-chud historians and called Dalmatinska povijest (History of Dalmatia). It was created specifically to counter popular Serbian nationalist pseudo-historic claims on the Internet regarding Croatian national identity in the Middle Ages and Early Modern period. Some of the topics explored were completely new to me, like the Medieval Serbian invasions of Dubrovnik/Ragusa, or the travelogues of Evliya Çelebi.
https://www.youtube.com/@historiaincognita/videos
Second one, Historia Incognita is run by Croatian crypto-commie historians. Videos on obscure topics mostly pertaining to Yugoslavia (both of them), socialism and WW2. Topics like the Diamantstein Affair or the Cattaro Mutiny. There are plenty of lesser-known events in 20th century Balkans which I find interesting.