OK, I had to look this one up on Google. I did find a website from HM Revenue & Customs that looks promising: HM Revenue & Customs: Qualifying Recognised Overseas Pension Schemes (QROPS)

From a quick look at it, it seems like these are just overseas (to the UK) pension funds that are recognized by the UK government (for whatever). The French pension schemes mentioned are all private pension funds, as are the pension funds listed as being US based.

The "French tax implications" of such funds would depend on your country of residence and possibly your country of nationality (if that is different). Are you living in France, or thinking of moving there? Or just thinking of investing in one of the French based funds?
Cheers,
Bev