Japan is a lovely place to visit all through the year. Yes there are difficulties when you are a vegetarian travelling abroad, still like every country there are veg food available in Japan too. Here are a few vegetarian dishes to taste Tempura Japanese curry
Ramen
Rice crackers Goma tofu. There are lot of veg restaurants in Tokyo, Kyoto, Osaka and takayama. Here are a few tips to say you are vegetarian Learn the Japanese sentence
Print a vegetarian card for you to carry
Do a full survey on vegetarian food for only a few cities have vegetarian hotels Will share a few tripoto links written by travellers pertaining to their travel to Japan see if it is suitable for your travel. https://www.tripoto.com/japan/trips/vegetarian-food-in-japan-i-top-10-dishes-to-try-in-japan-for-vegetarians-5ce94f3328680 Sharing the below link written by a tripoto traveller, just in case it might be useful for you. https://www.tripoto.com/trip/how-to-pack-your-back-5cbe996b9f016