How to program and export with Eclipse?

One way is to tick "use external editor" in the settings of the arduino IDE and atill use it for uploading/compiling.

Another solution would be to use a plugin or something, a quick internet search gave me this: https://www.eclipse.org/community/eclipse_newsletter/2017/april/article4.php

Hey, I met the guys from Sloeber at the Rome Maker Faire, it's another module to run arduino programs in Eclipse :

http://eclipse.baeyens.it/

Does this plugin support the Gamebuino?

If you are able to select the Gamebuino Meta board and upload...then yes! Don't worry about trying out, you can't break your Meta that way