Currently copy/paste is done inside the app, so can't be used to move data out of the trial. We do plan to support copy/paste across Spine instances, which would allow what you need, but haven't gotten to it yet as our enhancement wishlist is very long.
The trial is a separate app from Spine Essential and doesn't have any mechanism to get out the data. I'm afraid there's really no way to get your animation data from the trial.
I think the best that can be done is to leave the trial running and use it as a guide for the poses in your animation. You could screenshot the trial and put those images in Spine Essential (eg uncheck
Export for those images) so you can match up poses on top of them. I realize this of course isn't ideal, though it is a one-time pain.