Is there a possibility that "eventually" Eevee will be able to evolve into any type and possibly dou types?

Question

Eevee is known to have evolved into many types and in every new generation title, Eevee is granted another type evolution. As far as I know, Game Freak is hinting that once Eevee is under the right condition, eevee is able to evolve into that type.

Answer 1

It is definitely possible that Eevee will eventually evolve into all types, although for now we cannot say.

We shall see but based off past experiences it is likely that Eevee will be able to evolve into all types, but not duo types.
Again, for now we can't say exactly what will happen. But if Game Freak continues on their current path Eevee will remain a single-typed Pokemon.