Restore Apple Watch Fitness data to other Apple ID

Recently, I revived my old MobileMe Apple ID. Like many longtime users I had separate iTunes/App Store and MobileMe accounts. Back in 2008, we couldn't use our MobileMe accounts for purchasing apps. I created a new iTunes account and have been using it as my primary Apple ID ever since. Going back to the old account (which is my givenname@me.com) and losing my purchase history was never an option. For merging accounts ... I lost hope more than 10 years ago.

Family sharing enabled starting using my givenname@me.com as primary Apple ID again. So I'm in a family with myself. The account switch went fine, I still have to update a few third party Sign in with Apple delegates, but that's ok.

Currently I have a spare iPhone with my now old iTunes Apple ID, paired with my old Apple Watch. It has many Fitness awards, including the 1500 Move Goals.

My new iPhone and Apple Watch have 114 Move Goals. I knew what I was doing and that I would have to earn all awards again, but it still hurts a little. However I was able to transfer a lot of Health data to my 'new' Apple ID by syncing from the old iPhone to the Withings app, but of course that did not include fitness stats.

Does a third party app exist that can read fitness data from one iPhone and store the data in its own cloud account, like Withings? It doesn't matter if I have to subscribe or purchase an app.

Thanks!