For Automated events, by default times are always shown to viewers in their local time. For example, if your webinar is scheduled for 10 a.m. and your timezone is set to Eastern, a viewer in the Pacific time zone would see it scheduled for 10 a.m. in their time zone.
However, if you want, you can also run the webinar in your own timezone. Check this out learn how.
For Live and Hybrid events, times are converted to viewers' local timezone. So for example if your event is set to run at 10 a.m. Eastern and your timezone is Pacific, you will see the webinar at 7am.