Thanks for all the comments everyone.
I think I will go with style 1 so that the screenshot page does not become a chaotic blinking mess. However, I will also provide a link to some sort of comparison that allows a manual switch between the two shots. And there will of course also be normal screenshots without any comparison that show the new skyboxes in full.
Apart from that I've been making good progress. The main Telos render is now finally done and I'm also making progress verifying that everything is working as intended.