Reply To: From Nagano to Fujikawaguchiko
There is a bus connecting from Kofu to Kawaguchiko. Their buses are all accessible (can accommodate one wheelchair or two) as far as I checked with the staff today on the phone. It takes 70-80 minutes from the JR Kofu Station to Kawaguchiko Station, 10 buses per day from departure (Kofu Minami Station) at 7:40 to 19:10.
https://bus.fujikyu.co.jp/rosen/detail/id/8 (unfortunately I could not find any information in English)
The all-train route mentioned above probably is more comfortable, and JR staffs will normally support you changing trains i.e. escorting you to the train you should take, carrying a portable ramp.
