These notes are based off of The Observatory’s YouTube Tutorial.
I can’t speak to earlier versions of Blender, but with Blender 3.6 these instructions are no longer needed. The Image Texture supports both Image Sequences and animating the Offset value.
One may add an Image Texture Node Choose a numbered range of images Set the Frames to 1 Insert Keyframes for the Offset value to animate the texture. Note: Image Sequence Nodes are no longer available or needed.