Change patches and banks on Fluidsynth/Dexed?

The Pisound with Modep on a Pi 4 is great so far for audio quality and building pedalboards. I’ve setup and loaded hundreds of more plugins based on great posts here.

I’m used to the VST model in a DAW for loading patches and banks. So far it seems like the LV2 plugins don’t work that way. I don’t understand how to load new banks/patches.

How would I change the bank in Fluidsynth (any of them) to a new sampled piano SF2 file or some other one I downloaded? When I click on the gear for the plugin, it lists factory and user presets but no way to load a different one from the file system.

Same question for Dexed or any other Synth (JX10, DX10, etc) . I installed a version of Dexed that came with no patches so it’s not very useful if I can’t load patches.