I am visiting Japan soon and was wondering if I can watch on Crunchyroll over there? Or do I need a VPN to get it to work ?
Crunchyroll does not acquire rights for Japan, so it would be functionally useless. While I was in Japan last year, I used a VPN so that I could still watch the new episodes in the evenings.
I also downloaded several episodes for offline viewing on the plane, and ended up watching some of those in Japan too.
Honestly I would subscribe to the middle tier option and download a bunch of episodes to use the offline viewing perk.
Wait I was in Japan this summer watching on Crunchyroll no VPN needed
Like the others said a VPN will be the way to go, I was disappointed to find out it’s blocked in Japan 
I ended up watching the Cowboy Bebop movie on YouTube lmao
Crunchyroll won’t work, but there’s a surprising amount of subtitled anime on Netflix JP and Disney+ that’s not available stateside. Last trip I watched a fair bit of Apothecary Diaries, Oshi no Ko, and Frieren there. You won’t really know if there’s subs for the series until you actually load an episode up though. Even the JP-only shows have English descriptions.
Sadly no, last time I just downloaded a truckload of One Piece episodes before I went. Got to get through that backlog somehow!
I can’t believe people actually watch anime legally now.
I personally would not subscribe to a company that wants to pivot to shitty AI translations and instead simply download it from elsewhere.