The hook won't exactly work because queryCache.findAll will yield a new array, and snapshots need to be referentially stable. That's why e.g. useMutationState uses a ref:

useIsMutating uses this hook under the hood, so if we do this, I would say we come up with a useQueryState hook and derive useIsFetching and maybe usIsPaused from it, though useIsPaused could then be niche enough to be done in user-land with useQueryState.

on the other hand, you could also simply hook into the onlineManager and display an offline banner there? Not quite the same, because you can be offline and not have paused queries ...

so, I'm mostly concerned about api surface, but useQueryState with the same api as useMutationState sounds right to me. With filters and select, you can basically get anything you need. The mutation state hook also uses structuralSharing to make sure the select results won't change needlessly.

I'm even thinking that useIsFetching and useIsMutating could then be deprecated in favour of just:

useMutationState({ filters: { status: 'pending' }}.length

which isn't that much more and I don't think those hooks are widely used.