Russian text and professional Russian voice acting are part of DREADMOOR's announced language support. You do not need to assume the game requires a fan translation simply because an older playtest video is in English. However, a verified sequence of language-menu clicks is not available here, so this page cannot give a dependable button-by-button toggle procedure.
Russian text and Russian audio are separate
DREADMOOR's October demo announcement lists Russian among its supported languages and announces professional voice acting in both English and Russian. The launch-language announcement repeats those two audio languages.
The main-game language table separates text, full audio and subtitles.
Text support covers a different requirement from spoken dialogue. A game displaying English subtitles while using Russian voices, or the reverse, needs its text and audio choices checked separately. The available information does not establish whether the current build combines those options in one control or exposes separate controls.
Check which build you are using
The earlier pre-alpha test was English only. That restriction belongs to the historical test and should not be copied to the October demo or the announced launch language set.
Check whether your library entry is DREADMOOR, DREADMOOR Demo or an older playtest before comparing settings with another player. A menu captured from one entry may not describe another.
When Russian does not appear
Inspect the language choices actually available in your installed build and report the edition, build information and missing text or audio option through the game's feedback route. Include whether the problem concerns menus, subtitles or spoken dialogue.
There is no verified configuration-file edit, launch flag or exact menu label established for this problem. Applying instructions for another game would not be a supported solution. Likewise, changing the Steam website's language only changes the website; it is not proof that DREADMOOR's own text or voices have changed.