An app for Steam Deck users would be nice
Welcome to the community! 
At the moment, WeMod does not officially support the Steam Deck. Since it runs on Linux, supporting it fully would require a dedicated Linux development team and Linux testers. This may change in the future as WeMod continues to expand.
Currently, interest in Steam Deck support within the community appears to be relatively low, but we are always listening to feedback.
In the meantime, there is an unofficial guide available here: My perfected and streamlined WeMod tutorial for Steam Deck . Please note that WeMod is not able to provide support for this unofficial method.