GMT date/time format regarding exporting data to external application - Is there

Have you tried the local() function? The docs has a large section on how Appian handles date/time values in various scenarios so I'd check there too.

Tim, we have tried the local() function, which will correctly adjust the time value; however, we would like to find a way to pass the correct timezone to the plugin as well.

For example, we ran a test at 3:14pm EDT prior to implementing the local() function. The date/time displayed in our external application as 7:14pm GMT. After using the local() function, it displayed as 3:14pm GMT.

As you can see, the time updates correctly with this function, but it still displays externally as GMT.

I would look to pass it as a separate value. Look at timezone() and timezoneid() functions to get the current users values
forum.appian.com/.../Date_and_Time_Functions.html

Thanks, Tim. We have conveyed the option to send an additional value through the smart service to our client previously, and will reiterate that point. We just wanted to confirm that there is no way to do so with just the date/time field within Appian.