I tested Renoise 3.1.1, 3.2 and 3.2.2 with Surge and Zyn-Fusion (zynaddsubfx-vst) from the KXStudio repo on Linux Mint 20.
The 3.2 series is scanning and finding the plugins, but the dropdown doesn’t even activate. When I click the arrow it flashes orange, nothing else happens, so I can’t load them. I tested 3.1.1, as it’s the most recent version in the 3.1 release series, and everything worked as expected. 3.1.1 scanned, found, loaded, and worked with these Linux VST plugins.