Usually, yes. Using a VPN isn’t explicitly called out as banned in
Dead by Daylight’s EULA, but BHVR does prohibit using “programs or tools” to gain an unfair advantage, and it bans things like unauthorized connections and exploiting bugs or features for competitive advantage. So a VPN used normally for privacy (like staying safer on public Wi-Fi, hiding your IP, etc.) is typically fine, but using it to intentionally create unfair advantages is where you start drifting into “this could be treated as cheating” territory.