TimezoneDB
TimezoneDB is a plugin that has been implemented for multiple mods:
It has not been merged into Vencord since it was created in December 2022.
The plugin lets you assign a specific timezone to any user (saved locally) and displays their local time in commonly viewed locations, such as their profile and message timestamps. The plugin also uses an instance of TimezoneDB hosted by AAGaming to retrieve other people's timezones that have set one publicly.
To make your timezone public, go to https://timezonedb.catvibers.me and sign in using Discord. Your timezone will automatically be set to your browser's current timezone.