Honestly if it was my choice I would go this route in this order:
1.Quick Ban Pheromosa: While I feel Aegislash is more broken I don't think we really should waste our time with this thing, it's broken in an Aegi meta, why would we want to test it in an Aegi-less meta ? just quick ban it now.
2.Quick Ban Aegislash: While this is a strawman argument, I feel like people who want this thing to stay are either A) sadists B) people who happened to build anti Aegislash teams so they think it's not broken or C) people who want it to stay so it can check other broken things. plz quickban
3.Suspect Genesect: While Genesect doesn't deserve a quickban, I think a lot of people really undermine how good it is, people talk about bulky water types to check it and act like TBolt is just a niche option when I personally never encountered a Genesect without TBolt and I have played tons of games. Not to mention the fact that Rock Polish with Ebelt/LO is similair to RP Lando in the fact that it's impossible to stop with offense.
4.Suspect Hoopa-U: I think fat teams are bound to become important with threats like RP Lando, Greninja and ShiftGear Magearna in the tier, so people will shy away a little bit from offense and turn to either BO, Balance or straight up fat, and that's where Hoopa-U will shine and be deemed suspect worthy.
5.Suspect Greninja: I think with faster threats gone, Greninja will run less of water shurikens and more of coverage to wallbreak like Extrasensory to deal with Toxapex and Amoonguss in one slot, and that's when it's gonna be clear that it needs a suspect.
6.Suspect Manaphy
6.Suspect Landorus-I
7.Suspect M-Mawile
8.Suspect M-Sableye
9.Suspect Arena Trap
10.Suspect Tapu Koko
11.Suspect Toxapex
12.Suspect Porygon Z
13.Suspect Tapu Lele
I think if at least more than half of these babies get banned, we'll finally get a kind of healthy metagame but we'll see.
Edit: of course, when I say suspect I don't mean straight up ban, what I mean is that we should look INTO these mons.
Edit2: also please never bring back Shadow Tag, and plz get rid of Baton Pass and Swagger.
1./2. Pheromosa is not that bad, especially with Aegislash. I think a quick ban on Aegislash followed by a suspect of Pheromosa would be better. Pheromosa struggles with Toxapex, Aegislash, Alolan Marowak, to name a few. Depending on which hidden power (or other coverage like poison jab) it chooses, it can struggle with pelliper, mantine, tapu koko, tapu fini, and Scizor. Priority wrecks it (you can run your own terrain to get rid of psychic terrain), weather abusers out speed it, and base 85s (90s?) out speed it with choice scarf. It can be dealt with in a variety of ways.
Manaphy, tapu lele, and *porygon-z*?! Look, you can't just ask for suspects because your team/moves lose to these mons. Manaphy hasn't changed since ORAS, tapu lele has a healthy amount of checks/counters, and porygon-z is predictable, can only set up once (can be hazed or roared/whirlwind), and suffers from 4 move-slot syndrome.