If the manual installation above seems too technical, search for a pre-muxed file named: Battle.for.Sevastopol.2015.1080p.ENG.RUS.DUAL.2021.Remux.mkv
The “2021” part of your search is critical: that year saw a surge in fan-made and scene-release groups producing remuxed versions of the film with sourced from the limited UK Blu-ray release. These 2021 repacks fixed earlier issues like: If the manual installation above seems too technical,