This might sound completely ridiculous at first, but would it be possible to unban kyogre from sm ou? It'm not talking about primal kyogre of course, but just regular kyogre. it might have some impressive stats, but so does kyurem-B and it is far from broken. Also, with the introduction of new pokemon in generation 7, it now has plenty of counters. For example:
252 Atk Tapu Koko Wild Charge vs. 4 HP / 0 Def Kyogre in Electric Terrain: 444-524 (129.8 - 153.2%) -- guaranteed OHKO
252 Atk Kartana Leaf Blade vs. 4 HP / 0 Def Kyogre: 414-488 (121 - 142.6%) -- guaranteed OHKO
Both of the above examples outspeed regular Kyogre. While Kyogre may have great attack and special attack, its speed is far from stellar, and its stat distribution makes it not difficult to wall. For example:
252+ SpA Kyogre Water Spout (150 BP) vs. 252 HP / 4 SpD Eviolite Chansey in Rain: 214-253 (30.3 - 35.9%) -- 44.9% chance to 3HKO
By that time Chansey probably would have poisoned Kyogre and could soft-boil stall, all while water spout keeps gradually losing power to poison. Let's not forget the all too common ferrothorn.
204+ Atk Ferrothorn Power Whip vs. 4 HP / 0 Def Kyogre: 360-426 (105.2 - 124.5%) -- guaranteed OHKO
Ferrothorn can also switch into normal Kyogre, as all of its common moves take at least 3 turns to KO it. There are also more interesting checks:
252 SpA Mega Charizard Y Solar Beam vs. 4 HP / 0 SpD Kyogre: 228-270 (66.6 - 78.9%) -- guaranteed 2HKO
While Charizard Y cannot safely switch into Kyogre, it could put a lot of pressure on it as a revenge killer since drought would deprive Kyogre of it's rain and halve all of its water type move's power. Additionally, Charizard Y outspeeds Kyogre, so if Kyogre was to try to take out Charizard Y with water spout (that being his strongest STAB move at full health), Charizard Y would be able to shoot off a solar beam before Kyogre could attack, thus reduce water spout's damage output to somewhere in the following neighborhood:
252+ SpA Kyogre Water Spout (42 BP) vs. 0 HP / 4 SpD Mega Charizard Y in Sun: 54-66 (18.1 - 22.2%) -- possible 5HKO
This being because water spout's base power is decreased when its user's HP decreases.
Kyogre also fails to stop a traditional sweepers after they have been set up, such as swords dance Mega Garchomp (or swords dance normal Garchomp for that matter):
+2 252 Atk Mega Garchomp Outrage vs. 4 HP / 0 Def Kyogre: 523-616 (152.9 - 180.1%) -- guaranteed OHKO (after swords dance)
+2 252 Atk Garchomp Earthquake vs. 4 HP / 0 Def Kyogre: 357-421 (104.3 - 123%) -- guaranteed OHKO (after swords dance)
+1 252+ Atk Gyarados Supersonic Skystrike (160 BP) vs. 4 HP / 252 Def Kyogre: 354-417 (103.5 - 121.9%) -- guaranteed OHKO (after dragon dance)
Kyogre doesn't pack overwhelming defense (with a base stat of 90) and its HP, at base 100, is good but not to hard to conquer. To put this into perspective, manaphy has greater defense (with a 100 base defense stat) and equal HP and after a single tail glow, much more special attack. Manaphy also has higher speed, so it can potentially sweep much better than kyogre. Furthermore, Kyogre's move pool is rather underwhelming, as it lacks the cherished focus blast to check ferrothorn with as well as any priority move. I believe that normal Kyogre can make a healthy addition to the sm ou metagame.