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I'd give it the Vanguard/Buddyfight starting Pokemon system and make turns more like an adventure featuring gyms compared to magic's kinda shitty mana system wizards copied into Pokemon.
Like, every turn you could flip a card from your wild encounter deck that can replace mana, like Force of WIll's system. They give you action points to choose to do things for your turn.
You can take your turn to challenge a gym, catch a Pokemon, challenge your opponent, fight a legendary, etc. We can have different win conditions like beating 8 gyms and a final champion, beating your opponent (aka rival) and Legendaries a certain number of times, catching all the wild Pokemon available, etc.
Balance it out with different starting Pokemon giving different bonuses or abilities that make them start weaker and end stronger than basic Pokemon like Kangaskhan who have a lower cap or go for different win conditions.
I think in the end that would feel more like a board game than a card game but it would depend a lot on the card design.