Is there a place to get games in this format? I tried following the links to the Japanese simulator but it looks like its text only and beyond my comprehension :(
Yes, I think it's difficult for Westerner to enjoy the Nintendo Cup 2000 on a Japanese simulator. So I have a manual for Westerner. I hope this is helpful.
https://seesaawiki.jp/pbs-thread/d/Gym Leaders' Castle Manual
And, Beelzemon suggests playing Nintendo Cup 2000 at Showdown. According to him, this was approved. We will probably enjoy this at Showdown in the next few months.
https://www.smogon.com/forums/threads/please-add-a-pokémon-stadium-2-simulator-in-showdown.3679486/