I'm currently working on a 100% route for this game. The basic rules are below.

Complete the game as normal, then go back, befriend everyone and get every item at least once.

Timing starts when you select "Play in Pokepark for the first time.

Timing ends either on the textbox "----- is now your friend" after befriending the last Pokemon you need or the text when you get the last collectable you need

You're the hero we need but don't deserve. Park 2 100% is awful (even compared to Park 1 100%).

-Beat the game
-All friends
-All items
-All upgrades

That moment when a wr holder calls you a hero. :3
I have updated the rules. Here they are.

You must:
Beat the game normally
Get all friends
Get all items at least once, except for the Vast White Quills, which you need to collect all 40 of.
Upgrade all of your pals stats to 100%

Timing starts when you select, "Play in Pokepark for the first time. Timing ends after the textbox, "------- is now your friend," after befriending the last Pokemon after completing all of the objectives. And yes, that does have to be last.
Saving and quitting is allowed.
If using emulator, you must use Dolphin 5.0.
Save states aren't allowed and if using emulator, you must use the whole emulator and have it be visible.

Here's a link to my work in progress Paste in Route if you want to check it out
https://pastebin.com/X6dNULxg

Holy crap, you guys! My 100% route is almost finished! I had to take a break due to school, but I’m back and almost done. Literally all that’s left is a little grindingIts still the same link if you wanna check it out

It’s finally finished! I’ll be doing a non recorded test run tonight

I'm going to be doing my first run of this sometime soon once i get notes done for myself. gonna die 🙂

I noticed klecleons awards are not in the route, do they not count for 100%?

I did a run of this with my own notes before the initial route was posted, I've been gone a long time, I ran into issues with the rulings though and wasn't sure what to do about kecleon rewards. If there is any notice about these I would love to run it again as my last run was terrible.

I forgot Kecleon awards existed when I made the 100% route, but I do not feel like they should count for 100%. It’s like the Battle Tournament, there is no reward for completing these challenges, and cannot be immideatly accessed through the menu like the collectibles. Also they would take hours of grinding. Maybe for the discussed “True 100%” this could be in there, but for now, Kecleon awards are out.

Due to Kecleon Awards controversy, I have decided that my guide will now be on the All Friends category similar to that of Pokepark 1. So no collectibles, only getting every friend

I think can be so much and so strange and so hard to colect practicaly all items, but is true that would be so nice a category of "All Friends"