Install reshade (legacy filters only), then activate technicolor2 and play with sliders until you like what you see.
I myself use Neat Perfection, basically another user's collection of filters preset to their own personal taste that I then modified, and it does a good job bringing out more color in the world while getting rid of some of that whitewashing you may notice (I notice it myself whenever I get on pts since I only have reshade installed on the live client).
https://www.nexusmods.com/elderscrollsonline/mods/89
You can also browse there, as most of those presets have instructions on how to install or uninstall the setups, so you can try different presets fairly quickly and, since they're already premade, you don't need to worry about spending as much time muddling with settings.