2d animation export only keyframes

Thanks for suggestions. Workflow that sorts of work for me is as follow:

Once You have the grease pencil animation that You like:

Loom Addon Sadly it does not detect grease pencil keyframes. Thus it is needed to create object level keyframes. Empty will do fine. Create one and paste them on frames where Grease pencil keyframes are.

Select all keyframes (in Dope Sheet) You want and choose "Render Selected Keyframes"

It then creates the keyframes list:

And finally it creates animation from keyframes only: