Dungeon Settlers has been reviewed by Valve for Steam Deck compatibility and received a Playable rating. Valve's compatibility review explains,
This game sometimes shows mouse, keyboard, or non-Steam-Deck controller icons
Entering some text requires manually invoking the on-screen keyboard
Some in-game text is small and may be difficult to read
This game supports Steam Deck's native display resolution but does not set it by default and may require you to configure the display resolution manually
While the game may be playable on Steam Deck, we do not officially support the device at this time and cannot guarantee an optimal gameplay experience.
However, we are positively considering broader Steam Deck support in the future as Early Access development continues. While we don't have specific plans or a timeline to announce at this time, we hope to improve the experience for Steam Deck players as development progresses.
Thank you for your understanding and support!