I've also bumped into this issue: #435 (IsAny not working for array of ints)

However, it seems like the recent fix in commit b24a8fb fixes the issue only for non nullable ints, but there's still an issue for non-nullable ints.

I'm getting:

"message": "Object of type 'System.Linq.Expressions.Expression1`1[System.Func`2[Entities.Property,System.Object]]' cannot be converted to type 'System.Linq.Expressions.Expression`1[System.Func`2[Entities.Property,System.Boolean]]'."

See the gist without the most recent commit here (uses version 5.5.3):
https://gist.github.com/samyonr/6bd85fad243bc39ab792d8788effc101

See the same code, but that uses the latest commit (by including the EntityGraphQL package in the code) here:
EntityGraphQL_IsAnyInt_full.zip

I'm testing isAny in string, a foreign key, nullable int (fails) and non-nullable int (fails with 5.5.3 but works well with b24a8fb).