Quick way to learn opposing factions

No but think that's a really good idea

Not sure how there'd be a short-list for Ret owing to the CID update and all themes being viable and most of the casters being perfectly capable of making a good showing compared to other factions (owing to a generally lower level of caster power to offset in-faction element strength).

[personal take ahead, I may be mistaken owing to qualitative assessment of my exposure to the world-wide meta, so I have no stats to back this up with]

Metas with moderate to heavy Ret presence will see a fair bit of shaking up when players get their heads around Goreshade4, Ravyn and the theme tweaks (Imps/Disco/Moros added, ambushing MHI etc.). Only one caster outright won't be anyone's top 3 (Vyros1), while there's a high chance Garryth won't feature either, but of the remaining nine, Ravyn may or may not creep in, Thyron will appear based more on player preference (he is quite polarising among the Ret players I know) while the seven left will be of more or less equal popularity with no real outliers in either direction.

Consequently, we have no real 'standard' competition lists because:

Elara - Defenders Halb spam(/Legions Sentinels)/Shadows MHI heavy
Helynna - Forges ARM&box spam/Legions Sentinels
Issyria - Legions [flavour to choice]/Shadows MHSF heavy
Kae - Legions Sentinels/Defenders 2x2(x2)
Ossyan - Defenders AFGs/Legions combined arms
Rahn - Forges Wall of Manticores/Forges Mitten spam/Defenders 2x2
Vyros2 - Forges Griffon spam/Legions Sentinels & Vyre lights

likely to add Goreshade4 - Legions [flavour to choice, Desters & Sentinels feature a lot]/Defenders Nyss Exiles

all have seen a measure of success at some point or other with no real stand-out and will continue to do so IMO because of the generally wider breadth of 'answer' lists Ret tends to have, the quality of life improvements & overall bump up from CID and players being comfortable with what they know at the local level despite the generally lower odds.

Personally speaking, though, I would go for Vyros2 Griffon spam (with or without feat fuel Mittens), Issyria (the Ret turd-polisher in chief, in Shadows) and Kae 2x2(x2) in Defenders (the list I would happily dump into any match-up I wasn't sure of, 'cos her assassination threat, while blatantly telegraphed, is deadly nonetheless).

I support this effort and would love to read someone's write-up, assuming that whomever writes it has real knowledge that has come through experience.

With the caveat that the meta shifts and these lists would have to be updated often. IIRC some of the top players have done this maybe twice a year but not monthly.

Any Ret players keen to post their post-Cid list rundowns & tricks? I managed to play way too many pointy ears on a tourney this weekend and was completely unprepared