Princess Twilight Sparkle of Equestria and Gwyn's Firstborn Solaire of Astora stuck in 1971 Earth of superior Australians, cloned mercenaries and unusual hats.

There are a lot of adventures awaiting them, in their many year stay.

(Need editors and pre-readers!)
And this is very Dark Soulish. It is more a TF2/Dark Souls crossover than MLP/TF2.