Im thinking giant foxes, potencially from tian xia, as an higher level beast/animal that is used in the kitsune armies or being workship like guardians.
I'm not sure what kitsune armies you're talking about? There aren't a lot of primarily kitsune settlements, let alone somewhere large enough to field an army. They're shapeshifters, and thus tend to intersperse with the ancestries they can take the form of.
For high-level foxes, we have gumiho at level 17, bul-gae at level 14, and immortal trickster at mythic 11th. None of them are large, but generally one isn't picking a fox thematically for size and power. Lots of shapeshifters, you don't get a lot of simple big animals at high levels outside of dinosaurs.
Some good options with what we have are wolf animal companions, finding canine and feline animals and beasts to convert, using beast eidolons, or homebrewing.