Hi @justin-hausmann-sector-e, Retool doesn't have built-in support to change component output languages currently. For the Timeline component, you should be able to plug in the weekdays raw as they are not pre-set. For the Date Time component however, the weekdays are set in English.
Alternative approaches could be to integrate external translation APIs, or explore our new AI features. There aren't any open requests for this feature at the moment, but I'd be happy to submit one if you'd like?