Honestly just a general resource to leave here, and my opinions on the decks we have in standard. Feel free to recommend changes and tell me if I missed anything
Tier 0
Decks in this tier are undoubtedly the best deck in the format, and they should be winning almost every tournament that is played. These decks have little to no weaknesses, and are extremely consistent and powerful.
None
Tier 1
Decks in this tier should be expected to be extremely popular in tournaments, and you should expect to see them often. These decks have a few weaknesses, whether in consistency or power level, but are still expected to be winning often.
Zoroark/Lycanroc
Buzzwole/Garbodor/Shrine
Vikavolt/Rayquaza
Psychic Malamar
Tier 2
These decks should still be seen frequently in tournament play, but they are generally worse than tier 1 decks. They generally lack the consistency or power of the top decks, or have a poor matchup spread against other decks
Buzzwole/Weavile/Shrine
Buzzwole GX/Lycanroc
Zoroark/Banette
Zoroark/Golisopod
Magnezone
Ultra Necrozma/Malamar
Zoroark/Magcargo
Bulu
Skillveon
Zoroark/Weavile
(tier 2.5)
Sylveon/Gardevoir
Zoroark Garbodor
Metal Beast Box
Tier 3
These decks fulfil a small niche in the current metagame, but are seen infrequently. They generally have some crippling flaws, but offer something that other decks do not.
Reshiram/Ho-Oh/Kiawe
Zoroark/Lucario
Metagross GX (all variants)
Malamar/Shrine of Punishment
Decidueye/Zoroark
Greninja/Zoroark
Tier 4/Meme Tier
These decks are outclassed by other decks, but people play them for fun
Zygarde/Lycanroc (sorry klive)
Hoopa
Zoroark/Guzzlord
Rotom
Ho-Oh/Salazzle
Garchomp/Lucario
Slaking
Empoleon/Swampert
Lapras GX/Quagsire
Some garbage crocodile deck
The 2018-19 format brings with it a diverse range of playable decks, resulting in an open metagame with multiple tier 1 and tier 2 decks. However, the lack of good draw supporters means that many powerful decks are hurt by consistency issues, especially in the early turns.