HELP!! I need any good build for as many as possible Pokémons (IDK where to post)

[duskgrave]

As the title says, as many as possible
I'm holding a mini tournament between my nephews and nieces, they get to pick a Pokémon randomly, but I can't find a build for so many Pokémons
As far as I went, I provided them with the 27 fully evolved starters (not including regionals), and all mythicals (not including meltan) and if they got arceus, they get to spin a wheel to decide which type, and I also added the 2nd form for both shaymin and hoopa.
therefore i got only 68
next I plan to add all legendries, but not all of them in the format I use (gen 9 national dex ubers)
and if possible, is there any format without any restrictions? full out brawl between any two Pokémon?​

 

[Uranium233]

A. Smogon strategy dex is your friend, but if it's just a single pokemon then you're likely going to have to build them yourself
B. I believe the format that you're looking for is Nat Dex AG
C. Random choosing is not gonna be fair. I would hate to get a Meganium while my cousin gets Arceus or Giratina. You can continue like this, but it is something to consider.
D. Pretty sure smogoff isn't the place for this, but I don't know what is

 

[Just A Shroom God]

As the title says, as many as possible
I'm holding a mini tournament between my nephews and nieces, they get to pick a Pokémon randomly, but I can't find a build for so many Pokémons​

Random battles sets are probably the way you want to go. You can use the command /randbats (pokemon) in the game chat or lobby chat to see a list of moves for that pokemon. You can also use the Randbats Damage Calc to see more info, such as Tera Types, Abilities, and Items.

next I plan to add all legendries, but not all of them in the format I use (gen 9 national dex ubers)
and if possible, is there any format without any restrictions? full out brawl between any two Pokémon?​

National Dex Anything Goes (AG) is a challenge-only format that allows literally anything that exists in pokemon to be used without limits, including stuff like Baton Pass and FunBro, which should be perfect for your purposes.