Is there a Pokémon GSC base with an expanded Pokédex?

[The Dash]

Is there a Pok?mon GSC base with an expanded Pok?dex?

I don't know if anyone is already working on this, even if they are I'd kind of like to try my hand at it. I'd like to create a Pok?mon GSC hack which incorporates an interpretation of the recent Spaceworld demo leak. However I don't want to remove any existing Pok?mon from the hack. I know expanded rosters exist for Fire Red but is there one that has been made for GSC?

Apologies if this is an obvious question, I haven't touched the ROM Hacking scene for gone a decade now, but I'd honestly like to work on this idea.

 

[lilbluedemon]

I presume there somehow is.

Considering Pok?mon Prism has 296 Pok?mon in the Pok?dex.
Which is an extra 45 spaces than the vanilla crystal.

But, I think but am not 100& sure, you'd have to mess around with the coding of Crystal, probably using pokecrystal