I don't know if will help, but Romhacking (their wiki more specifically) has notes and such for tcg2 that is already documented which could help
The major release standouts of this period were the Burning Shadows Charizard GX (2017), and Tag Team card Reshiram & Charizard GX from the Unbroken Bonds set (2019), two very playable cards that quickly found their way into the meta game
Key Cards Cloud, Ex-SOLDIER Cloud, Ex-SOLDIER acts as both a target to put all your Equipment on, as well as draw power and ramp
When used alongside a card that lets you reshuffle your graveyard back into your deck, Time Walk can still be quite the strong card, and that means its a highly sought-after one, too
However, I do have Griselbrand, and that guy likes to gain life
Lotus Vale / Mox Diamond / Phyrexian Dreadnought More cards that had their functionality disrupted by a rules change