For 2 inch there’s the m48
Weooen 2inch Telescope Camera Adapter with Internal Filter Threads, Metal Telescope T Adapter and T Mount, Compatible for Canon EOS, SLR, DSLR https://www.amazon.com/dp/B09L4S229J/ref=cm_sw_r_cp_api_i_K5223NP3GKP9YC7WD49A?_encoding=UTF8&psc=1
And the m42
Solomark 2inch Precision Ultrawide 42mm Camera Adapter for Nikon DSLR Camera and 2inch Telescope Focuser https://www.amazon.com/dp/B00T4KEC7Y/ref=cm_sw_r_cp_api_i_H2CGS0FGVGVEXPSVN85H?_encoding=UTF8&psc=1
Both have standard 2” filter threads
If you plan on using old lenses the m42 mount is the one to get and if not the m48 is the way to go as it is a more common telescope accessory thread