If you zoom in on the highways, you can see RGB ghost images of moving vehicles. Is that an artefact of using 3 distinct filtered inputs or something else?

[ps. The frequency shift is definitely reflecting vehicle direction - right side of highway is BGR, the other side is RGB. Delays in the sequence of 3 filtered captures?]

Yes, the different bands are not collected at the same time across the whole scene, so you get ghosting with moving objects. The SkySat sensor [1] is split in two halves: panchromatic and RGBN (where N is near-infrared). It takes lots of captures as the satellite travels that are later aligned and combined into one version.

[1] https://directory.eoportal.org/documents/163813/5615117/SkyS...