That's a possibility. Pokémon is a juggernaut, it would be very hard to beat them.
Speaking of Pokémon, I always find it funny that there are seven Pokémon in SEGA consoles.
Well, the console was SEGA Pico and its successor but it's as wild as finding there were 2 SEGA games in PS1.
Well, Sonic on Nintendo consoles isn't as farfetched either.
Still, while Mario is usually considered Sonic's direct competitor, I imagine if Sega ever released a trading card game internationally, whenever it be Sonic, Dinosaur King, MushiKing or something new entirely, I imagine both Sega and Nintendo fans will regard it a direct competition with Pokémon TCG. And if Nintendo did regard it as a challenge, would steam roll over Sega's cards.
https://www.youtube.com/watch?v=y_PrZ-J7D3kPersonally, and this is just me, if I were to start a brand-new trading card game for Sega, I have two ideas in mind:
Sega All-Stars Trading Card GameWhile the Sonic series has grown enough to have enough variations of characters to make collectible cards from, having cards that cover all of Sega's owned franchises would allow more variety for players to make decks from.
Chao Trading CardsInstead of a traditional trading card game, perhaps each card has a microchip inside them to make them
NFC cards.
I like to imagine, if we ever get a Sonic Adventure 3 or a remake of SA:DX and/or SA2B, instead of "Chao Adventure 3", what if we get a
location-base game for chao instead? People can upload their chao from computer/console of Sonic Adventure straight to their mobile device. Only instead of an auto-walk game like the VMU Chao Adventure games were, you'd be able to go out and about and take your chao for walks and discover virtual content.
What do NFC cards have to do with it? Well, I think chao gameplay in general should be overhauled. Particularly replace Chao Karate with Chao Combat. Chao Combat can be based either after Dinosaur King/MushiKing gameplay or perhaps a more basic RPG-like battle system. But collectible cards can be used during Chao Combat for enhancements, special attacks or bonuses etc.