I have purchased Capture One 12 with a bundle of Styles. Will I be able to use them in Capture One 20 or do I have to purchase them again?
Once you purchased Styles either separately or together with Capture One Pro/Fujifilm/(for Sony)/for Nikon perpetual license or subscription, you can use them onwards even after an upgrade or switching to another license. For instance, in case you purchased Capture One 12 Pro with a bundle of Styles and have recently upgraded to Capture One 20, you can simply use those Styles in the latest version of the software, so you do not have to purchase those once again. The same goes when you switch between any license types. The only thing you have to do is to import Styles or Style Packs in the newer version of Capture One.