I added already three different extensions for importing .obj files but sketchup is not showing the .obj type at File->Import…
There might be new entries in other menus and normally they are mentioned in the plugin documentation or description.
I only know of one [$} OBJ importer [‘Fluid’] that shows up in the File>Import options…
All others are usually to be found in the Extensions [aka Plugins] menu…
You need to read each extension’s guidance notes on how it is to be used…
Thanks for your help