I think many people will feel the same for quite some of the cards shown in Legends of Runeterra, they created some really interesting cards which we would love to see as actual champions in League of Legends.
For me, Corina Veraza is that one.
It is a different approach to the alchemist theme. Singed, while a fun champion, doesn't really represent the alchemist theme very well in the game. Corina Veraza could have been an opportunity to give us another take of the alchemy theme, but with a slightly other approach by giving us a biologist, she is a chembaron who researches the plants she is raising in her cultivair.
This is something that I wanted in the game for a long time (even if my approach was someone who uses their biological knowledge to fight the diseases spread by the Zaun Grey). Hell, they even gave her a spell in the card game called Magnum Opus, emphasising her alchemy theme even more....
Unfortunately, we surely won't get such a champion in the future anymore since she is more of a side character in this card game now...
How about you guys? Are there any cards in that game that you would have loved to see implemented as champions?