Sounds like memory issue? You said your pc had a power failure. It could be faulty RAM or HDD/SSD failure? Sorry my Turkish is 0.
EDIT: Things to try …
- Unsubscribe from all mods and verify the game files.
- https://support.steampowered.com/kb_article.php?ref=1274-uohk-5653
- https://steamcommunity.com/app/440900/discussions/0/1710690448230314162/#c1761356057401263543
- https://www.reddit.com/r/ConanExiles/comments/8i0naj/conansandboxexe_application_error_0xfd931b54/