Yes. You can change a character or model data's usage conditions after you set them. However, you cannot edit usage conditions for model data that has already been downloaded by others.
If you downloaded a model, please use it according to the usage conditions set at the time of the download.
Characters registered on VRoid Hub reflect the latest usage conditions. The same goes for characters used in SDK-connected services; however, please that it might take up to 24h for the usage conditions on SKD-connected services to update after they've been edited.