You can assign the function org-copy-visible to your copying command key in the annotation buffers by doing something analogous to the following minimal sensetion use-package declaration:

(use-package sensetion
   :commands sensetion
   :bind (:map sensetion-mode-map
		 ("M-w" . org-copy-visible))

Creating a new annotation buffer with a sizeable number of sentences in a big corpus takes a few seconds. You can try to do two things to improve this:

• set the emacs variable gc-cons-threshold to a higher value, add the following to your init file:

  (setf gc-cons-threshold 60000000)
      

  (tweak the value as you like)

• bytecompile sensetion – see this SO question for how to do it and a few pitfalls (we don’t recommend this, since it can break updates if you are not careful)

If none of that helps and something is bothering you, open an issue describing the problem.