I have bought a “hama Delta Ovum LCD” Universal Charger : https://de.hama.com/i/00081370/hama-universal-ladegeraet-delta-ovum-led-fuer-li-ionen-akkus-und-aa-aaa-zellen
It has both a 220V cable and a car-cigarette-lighter cable.
The spec sheet says it can load 3,7V Li-Ion batteries (the Fairphone 3 has a 3.85V battery).
It works. It takes about 4h to load a new Fairphone 3 battery from completely empty to 80%.