Mapping a 3rd-party N64 controller (mine was detected as Retrolink N64 Controller) : r/RetroArch
USB N64 Controller and Retroarch is practically incompatible to configure correctly. The only solution I found was to map the n64 controller incorrectly to trick it. Breaks it on all other consoles.
RetroArch] Every Controller is Not Created Equal : r/emulation
The Ultimate Guide to N64 Emulation on Retroarch - Make Tech Easier
Looking for controller reference image - Collections and Builds - LaunchBox Community Forums