UMM mods are stored and only loaded if in a separate folder outside of the main Bepinex plugins folder. This poses an issue for R2Modman since it installs all mods, regardless of whether they are UMM mods or not, to the plugins folder instead of the UMM mods folder. So there is two options: either the UMM mods folder must be removed, and instead, UMM should check for compatible mods in the main Bepinex plugins folder, or an alternative approach would be to somehow configure Thunderstore/R2Modman to install mods to the UMM mods folder, provided that UMM is marked as a dependency for a mod.
UMM mods are stored and only loaded if in a separate folder outside of the main Bepinex plugins folder. This poses an issue for R2Modman since it installs all mods, regardless of whether they are UMM mods or not, to the plugins folder instead of the UMM mods folder. So there is two options: either the UMM mods folder must be removed, and instead, UMM should check for compatible mods in the main Bepinex plugins folder, or an alternative approach would be to somehow configure Thunderstore/R2Modman to install mods to the UMM mods folder, provided that UMM is marked as a dependency for a mod.