Nice find in Wikimedia Commons! I had followed some of that provenance chain and found it inconclusive, but interesting enough to leave in as links for the curious. I rather agree that these were originally French postcards that found their way to Hungary and into that now-defunct Hungarian-language erotica collection from the early web. Caveat being that “French postcard” in actual 20th-century usage tended to mean “dirty picture that the English-speaking world is blaming on the French” more rigorously than “French photographer and publisher” even though Paris was in truth a world-leading city of erotica production for many decades before the big wars of the 20th century.

And here is one of those images: link. That page claims it to be indeed a French postcard, but provides no additional details. Seemingly, there is no page currently using it.

There is a page on French wikipedia that uses a photograph, apparently from the same set, but doesn’t seem to claim it to be French: link (footnote: I don’t read French, but Google Translate is awesome).

The image on KD (link) has a URL: (link) — the text there is Hungarian, and it does have all three images, but lists all of them as ismeretlen — unknown. The last image on that page seems to be from some dude named László Sándor — a Hungarian name. On the other hand, the very first image on the page says “Bogdánffy mérnök úrhoz Budapestre a világ minden tájáról érkeztek az efféle levelezõlapok” — engineer Bogdánffy received such postcards from everywhere around the world; so, László Sándor, likewise, could’ve been the receiver of this postcard as well, not the guy who took the picture. Back on the first hand, the whole http://www.idg.hu/expo/mucsarnok/akt/ URL seems to be referred here: link — as “A magyar aktfotó”, the Hungarian nude photography.

So, no real answer. Sorry.