So I've been wracking my brain trying to figure out why I couldn't see the beta on my Japanese PS4's PSN store. I had trouble finding it. It wasn't under any searches. I DID however find it on the Japanese store online! For anyone who wants to access the Japanese Beta for Plus Members, navigate to PS Plus... then Specials. It should be there available to add to basket then manually download to your console. Why this wasn't explained in the first place, I don't know. Enjoy!