Update: It seems Italians backed off the enforcement for IOSS shipments and the situation in Romania appears to be the same. So only France is stubbornly enforcing the customs processing fee. We have not been able to receive further details from the French on the matter.
As of 1 January, Italy and Romania have implemented a temporary handling fee for all parcels valued at under €150 that originate from outside the European Union and enter the EU.
Italy: 2€ fee
Romania: ~5€ fee
Nevertheless, IOSS continues to be the most cost-effective and efficient delivery method for these countries.