Probably already been done before but ill still pitch this.
Retromons- all the pokemon and moves of gen 7, with the mechanics of gen 1. What does this mean? First, no items or abilities. Anyone that stays in OU thanks to an OP mega or great ability will suddenly have a tough time. Second, no special split. This means special attack and defense are one stat, which would be equal to the current greater of the 2, and any move that boosted either stat will instead boost special by that much. Any move that increased both special attack and defense will only increase special by stages equal how much it increased ONE of those stats(ex. calm mind boosts special by one.) Third, Physical Special split has yet to happen, meaning all types are either physical or special. No more ice punch coverage, that's a special attack now. Fourth, steel, dark and fairy types no longer exist. This is the toughest change, but anyone with those and another type will simply be that other type, and for those only these types, I am debating between simply making them all normal or replacing steel with rock, dark with ghost and fairy with psychic. whatever happens to the pokemon will happen to the moves too. Finally, fifth, all pokemon can max out every stat in EV's allowing for more utility on everyone and letting them use effective coverage without focusing on one attack stat.
However, any glitch or completely broken mechanic(permanent freeze, waking up taking a turn, speed-based crit, etc.) will not return
Threats:
Anyone with cosmic power. It now boosts special and defense, allowing it to heavily buff both offense and defense. However, the removal of magic guard will weaken users like clefable or sigilyph, possibly requiring them to use a status removing move to stay alive, but with the removal of dark type, stored powered is able to hit anything allowing them space to run one.
Manaphy/Xurkitree- with tail glow, they completely wall special attackers, and boost their attacks. Manaphy will also have balanced offenses allowing it to run mixed attacker sets, and xurkitree will have 173 special allowing it to switch in to any special attacker.
Anyone with extreme sp. def- main examples are shuckle and regice. They will both have 200+ base special, allowing them to wallbreak most anything
psychic types- with only bug weakness, they will be powerhouses, just like gen 1. Also, no dark type or steel types, making them have near-perfect coverage outside of psychic s=types, and psyshock will be valuable coverage to bypass many mons who will gain insane special defence from their sp. atk.
Quickbans: Regigigas, Slaking
Potential bans: shuckle, regice, baton pass shenanigans
Thoughts?