Viewer for different modalities at the same time

Good afternoon,

I am working with 3D-slicer viewer and I want to be able to visualize different sequences at the same time, lets say comparing 2 image modalities/sequences at the same time (one be main and other transparent on background maybe, something like that). I also want have this visualization while I am able to scroll through both different timelines and different slices. Is there any module or extension that can provide these features? Thank you very much in advance.