25
The list is not going to be short, I'd tell you hwat. To start off, there is a documentary (made by French-speaking journalists) - "Donbass". It's in Russian, with French subtitles, though I think there are translated versions on the internet somewhere. Here's the link
Russian people from the Donbass area suffered the most, of course - brutal mass murder, widespread torture and inhumane treatment by AFU soldiers (especially by the neo-Nazi militias), indiscriminate shelling and bombing of civilian infrastructure by the AFU (schools, grocery stores, places where people gather in considerable numbers).
As for the others - depends on the region and time period. Around 40 people were burned alive in Odessa (2 May, 2014), not to mention bloody repressions of Anti-Maidan protests in South-Eastern regions. Afterwards - everything pertaining to Russian culture was slowly and methodically displaced, up to 2022, though from what I can judge, if you were Russian just living in, say, Central Ukraine you would probably be fine (that, of course, changed after 2022).
Perhaps other documentaries like "Ukraine on Fire" and "Agent Zelensky" by Scott Ritter would give you a general picture, along with hints and clues. These are absolutely not perfect, but I verified them to be mostly factual.