Is it possible to translate your plugin in your own language?

>>Yes, you can easily translate our plugin into your own custom language via loco translate plugin. You can check the documentation here .

How can I translate the invoice?

>>We haven’t checked our Invoice & Packaging Slip plugin under multi lingual settings. You can use any translate plugin such as loco or WPML to translate the plugins.
For translation using loco plugin, you can check here.

I have translated the string but still it doesn’t display on the vendor dashboard

>>For this, all you have to do is, sync the strings first (see this screenshot – https://prnt.sc/m57rmn) and then start translating.