The EUR ING certificate from Engineers Europe can be awarded to those who have attained a degree in engineering, but also for those with "no exemplifying formal qualifications, but will have engaged in professional Career Learning and peer review via the individual route".
https://www.engineerseurope.com/what-eur-ing-certificate
Since Engineers Europe is a private organization (albeit one that is widely recognized), I would imagine that individual European countries have their own rules about when someone can call themselves an engineer. I am pretty sure that Germany only requires a degree for instance. Looser still are the rules in Britain: the UK does not require any certification at all for the basic term 'Engineer', although there are more specific titles that are strictly protected (ICTTech being one of them, and yes they really do use that silly abbreviation, obligatory italics included). Theoretically, a country could refuse to recognize certifications from Engineers Europe, but that would not exactly endear them to the European Commission or to other European countries!