Overall, the team is really good. I won't go and question the spreads too much because I'm sure they do their job well.
It covers a majority of the current metagame (Sun, it can deal with Thundurus + Zacian, Kyogre, it can go with a safe mode with fake tears + Dialga, intimidate cycling, safe mode with Amoonguss) but there are probably a few things you might want to consider:
1) It's really hard for you to stop Lapras + Zacian.
It's hard to stop Lapras + Zacian in general. You do have fake tears + max Lightning from Rotom:
116+ SpA Rotom-Wash Max Lightning vs. -2 204 HP / 4 SpD Dynamax Lapras: 390-458 (84.4 - 99.1%) -- guaranteed 2HKO
But 72% Lapras users use Lapras with Incineroar and 50% also use Amoonguss (don't ask me how it adds up to over 100% lol). You might want to consider bumping up Rotom's special attack stat (but even 252 sp.atk doesn't KO 100% of the time:
252+ SpA Rotom-Wash Max Lightning vs. -2 204 HP / 4 SpD Dynamax Lapras: 434-512 (93.9 - 110.8%) -- 62.5% chance to OHKO)
use LO Rotom?)
Looking at your team, it's hard to stop aurora veil from being set up. Once it is set up, it becomes hard for you and they have an advantage after they somehow set up with Zacian which isn't too hard. You might want to reconsider Rotom-W and either somehow allow it to KO Lapras or change it. Otherwise, you still might be able to defeat Lapras teams but it would be a great hassle.
2) Coba berry Venusaur
This looks funny but in actuality, 44% Venusaurs use Coba berries. It also means that Venusaur can spore Landorus twice before Landorus can KO Venusaur:
180 Atk Landorus-Therian Max Airstream vs. 4 HP / 0 Def Coba Berry Venusaur-Gmax: 135-159 (86.5 - 101.9%) -- 12.5% chance to OHKO
You also don't want to risk them being LO and just lead Incineroar + Landorus (fake out Venusaur t1, Airstream). If they are life orb:
252 SpA Life Orb Venusaur-Gmax G-Max Vine Lash vs. 4 HP / 76 SpD Dynamax Landorus-Therian: 142-169 (43 - 51.2%) -- guaranteed 2HKO after Vine Lash damage
I think you called your 76 sp.def spread to live this Vinelash. However, Vine lash damage will KO you regardless.
If you lead Incineroar + Landorus and decide to Flare Blitz + Airstream Venusaur, there's a high chance the opponent will lead Incineroar + Venusaur and you're forced to guess whether or not they switch into Groudon in the back. They might fake out Incineroar turn 1 and Vinelash then switch into Groudon and KO Landorus next turn and it essentially becomes a Venusaur for Landorus trade but you also have Vinelash on your side which isn't ideal. Low ladder people don't play like this but better opponents will most likely lead with Incineroar when they see that your Landorus is the only thing for their Venusaur.
Thundurus + Sun is also very difficult for you to deal with. LO Landorus + Regieleki?
They are your main threats, as well as the potential for Urshifu to deal a dent into this team because it outspeed almost everything late game and Banded Wicked Blow will hurt a lot.
Otherwise, it seems very well built!
