No, sorry. Projects saved with an old version of Spine can always be opened with a newer version. However, projects saved with a newer version of Spine cannot be opened with an older version.
http://esotericsoftware.com/spine-settings#Version

If you must, you can try exporting to JSON from v3 and importing the JSON to v2.

You will need to change "weightedmesh" everywhere it appears in the JSON data to "skinnedmesh".

If you update your runtime files, it should work fine with Spine v3.

Once all the runtimes are updated to v3, then we'll add a release to the GitHub page. spine-lua and spine-js have not be updated yet. You can watch progress here:
https://trello.com/c/tF8UykBM/72-update-runtimes-to-support-v3

You can download the latest runtimes as a ZIP, described here:
https://github.com/EsotericSoftware/spine-runtimes/tree/master/spine-cocos2dx/3#setup

fabiotg a écrit

Hello fabiotg, could you please tell us where you could get the older version of Spine?
We met the same situation with you but we just purchased Spine last week so what we download is the latest version of Editor...
Or could you please send us an older version?

We had same issue. however we stick to version 3.0.10 (from here skinnedmesh became weightedmesh) until we get all runtimes updated.

You can either replace all weightedmesh to skinnedmesh in JSON or just downgrade Spine version and export again