A fusion reactor creates a much more intense flux of neutrons than any fission reactor, which will transmute into radioactive isotopes any substance from which a shield will be made.

So the quantity of radioactive waste will certainly not be little, but more likely much greater than in a fission reactor.

Nevertheless, because there is more freedom in the design of the neutron shield than in a fission reactor, it is likely that it is possible to find such compositions where most of the radioactive waste will decay quickly enough, so that there will remain only a small quantity of long-lived radioactive waste.

However, until someone demonstrates this in reality, it is still uncertain how much radioactive waste will be generated, because this depends on many constructive details.

A lot of components of a fusion reactor, e.g. pipes for cooling fluid and the like, will become damaged by the neutrons and they will have to be replaced periodically, after becoming radioactive. The amount of such waste will depend a lot on the lifetimes of such components. For now it is very uncertain how much time such components will resist before requiring maintenance.