As much as I like fan-made Pokemon, I look at these, & having read so much about Glitch Pokemon recently, I can't help but be amused at how many of these would fall short compared to various Glitch Pokemon in BST.
Admittedly, most Glitch Pokemon lack abilities, & their movepools can be strange, but they would be pretty incredible if they came to Modern Pokemon without their glitches, & their stats, movepools, etc. in-tact,
Even scarier with the gen 1s if we treat Special as identical Sp. Atk & Sp. Def values. (Ex: 100 Special=100 Sp. Atk, 100 Sp. Def.)
For example:
https://bulbapedia.bulbagarden.net/wiki/?????_(Gold/Silver_00)
Effectively Pure Steel, as its Glitch type is Neutral to everything, like most Glitch types. No abilities, no level-up moves.... But Thunder, Fire Blast, Spore, Giga Drain....
And a BST of HP: 224, ATK: 1, DEF: 188, Sp. Atk: 163, Sp. Def: 213, Speed: 67 Total:
856
This isn't even the only glitch Pokemon with a BST of over 780, especially when counting ones where Special is treated as identical Sp. Atk/Sp. Def.
Not that it'd win in a VsBattle against most of those guys, but when it comes to super powerful unofficial Pokemon....