Shouldn't need a chain whip just to remove a freewheel from a hub. Nor even to put it back on.

Looks like the Shimano FW removal tool might work. Or some version of the splined tool. Various brands have similar splined tools that aren't quite the same.

Likely if you just take the wheel to a local bike shop, they'll loosen it for you and you won't have to spend so much on tools you might only use a few times.