Sounds like a good plan. Even if it isn’t a note from the doctor, thinking of some things you might expect to say regularly (“I cannot walk and need the scooter for mobility because of a disability” etc) and have them ready to show can be helpful.

Hi,

Those words are:

Crustacean is “Kokaku-rui”

Seafood in general is “Gyokai-rui” but that includes fish etc

I’m not sure if you saw this, but hopefully it will be an encouragement:

https://www.accessible-japan.com/go-global-traveling-in-japan-with-a-mobility-scooter/

Perhaps the author @gobyscooter can reply.

Ok, so I talked with Frank who runs a ramen tour place. If you book a private tour they can try to meet your needs he said. He is waiting for your email.

Here is the site:

https://www.tokyoramentours.com/contact

I have reached out to my friend who runs an accessible travel agency in Nepal.

Hopefully he’ll get back to me soon.