Hello!
Unfortunately, it will not help you with the train. It *should* help with tourist locations… but some places may not be fully recognized.
More details:

Disability Discounts in Japan

Thanks for posting!

To prevent this from getting burried in the activity feed, we’ve moved the post to a new topic in the forum:
https://www.accessibletravelforum.com/forums/topic/companion-card-australia/