The VST support in LMMS doesn’t work in the latest version of LMMS in the Solus repo as I can’t get it to work with version 1.2.0. I did add Carla support though, so you should be able to load Ladspa, LV2 and VST files through it instead. I don’t think it works using wine, need a native Linux version, but otherwise it works flawlessly. It is what I use for my plugins in LLVM...