isaac5700 This has just been improved in 4.3-beta! You can now toggle the Export checkbox when multiple skeletons are selected. The beta version should not be used for actual product development, so it may be some time before you can use it in your actual work. However, we are trying to keep this update focused on improving work efficiency, and we will do our best to release the stable version as soon as possible.

isaac5700 Before answering your question, please note that this forum has a translation button, so you are welcome to post in your native language.

Unfortunately, we do not update past editor versions. We only add improvements to the latest version.
We always recommend that users use the latest version of the editor whenever possible. To that end, we keep runtime changes to a minimum and provide scripts to streamline the process of re-exporting large numbers of Spine projects to a newer version: https://esotericsoftware.com/blog/New-export-shell-scripts

We have answered similar questions in the past, so the following thread may be helpful in understanding our approach: https://esotericsoftware.com/forum/d/27199-do-you-have-any-plans-for-convenience-updates-for-previous-versions-of-editors