Elsewhen

Time zones make talking to people online about times and dates complicated. Elsewhen makes it easier by letting you pick a date and time in a particular time zone that can be copied as Discord time code (which shows the time in each user's time zone,) or a list of times in time zones you choose, which can be shared anywhere you wish.

Nothing to add. It's free and awesome if you need something like this.

apps.apple.com/us/app/elsewhen/id1588708173