Even if you believe that the particular circumstances of the event led to a just verdict in Rittenhouse's case, I think one would have to be at the very least deluded to believe that Greene's statement of praise for Rittenhouse is not a call for others to take up arms and assassinate protesters.
Greene herself has called publicly for the murder of her political opponents and for advocates of vaccination mandates. How blind would one have to be to believe her singling out Rittenhouse (whom she also recommended for a congressional medal for "protecting the people of Kenosha") is not a call for combat and bloodshed?
Even if one believes that under the circumstances, Rittenhouse's actions were not illegal, the difference between that and calling them worthy of public adulation is huge, and yes, it's offensive.
Aside from all this, I believe even if you were a supporter of Greene, you would go along with this. She makes a concerted effort, after all, to be as offensive as possible to those whose deaths she publicly seeks. If you do not consider her remarks offensive, you might as well be accusing her of failure.