You can obtain the Charmeleon (2-Diamonds rarity) card by opening Mega Shine from Mega Shine set
Like most Pokmon cards, the value of Chikorita depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Unseen Forces)
Make that potentially repeatable via Commanders like Abaddon the Despoiler, Yidris, Maelstrom Wielder, Maelstrom Wanderer, Averna, the Chaos Bloom, or even The First Sliver, and fireworks are sure to ensue
So, if you happened to transfer a Pokmon with the right stats from one of those games into a later game, it would show up in its shiny form after the transfer
To truly catch a high-quality fake, you need to invest a few dollars into proper equipment
Japan-exclusive sets