Good comment from @AcidSmiley in another post:

if anybody wants additional sources, amnesty international already had reported in 2018 that the ukrainian government wasn't able to contain s14 and azov anymore since they were armed in 2014 to fight the seperatists in the east of the country. according to amnesty, the fascists regularly attacked roma encampments and the LGBTI scene, frequently without any legal repercussions. the number of hate crimes has increased continuously in recent years.

here's a summary of the situation (in German) from 2019:

https://www.amnesty.de/informieren/amnesty-journal/ukraine-regierung-hat-rechtsextreme-nicht-unter-kontrolle

ukrainian fascists are also systematically recruiting German fascists for the war, reaching out to some of the worst neonazi groups in Germany like III. Weg. Here's a recent article about this (again in German): https://www.zeit.de/politik/deutschland/2022-03/rechtsextremismus-neonazis-rekrutierung-russland-ukraine-krieg/komplettansicht

and a twitter thread from one of the authors, including screenshots from telegram chats were they talked with the organizers in ukraine: https://twitter.com/christianfuchs_/status/1499431993511227401

Note that actual organic support for fascism isn't significant in Ukraine, with nazi parties not being able to gain any seats in the parliament in the last elections. that's a remarkable difference to almost any other european country.

this isn't a movement of the ukrainian people, it is obviously propped up from outside, it has already become a significant threat for marginalized groups in ukraine and now with the war it poses the danger that fascists from all over the continent go there, receive combat training, gain experience in urban warfare and export terrorism back to the rest of europe.