I am a researcher on physics and I was invited to a conference as a speaker at the 1st European Conference on Engineering & Technology ECETECH 2022. The full expenses (round trip flight tickets, travel insurance, and hotel accommodation booking) will be paid by the organizer of the event. But I am expected to pay 650 euro as a registration fee in advance. My concern is, is the event real or scam to take money from researchers?
It is shady at very least. Covering a wide range of topics, with barely any mention of the organizing committee or keynote speakers - there is hardly any information to go by at all! Even the information for authors throws a 404.
Another shady bit is the venue - they say it will be in an hotel (and quite nice one at that!), however, this hotel website does not show anything close to be usable as a venue and the photo of the conference room apparently comes from a page of a much larger hotel... In Nigeria.
If the list of topics spans a page, you should already be suspicious. Conferences that have no focus typically imply that they are not where people with deep knowledge in a reasonably well circumscribed area of research tend to go, and that they need to draw from a much wider pool of people.
If there are shady aspects of the conference description, then you should be suspicious. For example, the description says "Only Invited Speakers (Incl. Spouse/Family or Co-Author's) are entitled to Free Round-Trip Flight Tickets, Accommodation and Feeding throughout the conference (courtesy of our sponsors)." That's just bizarre: Why would a conference pay for spouses and family to fly to the conference?
Pretty much everything else about this conference strikes me as odd as well. In the end, whether it's a scam I don't know -- it's quite possible that they will actually run the conference, but it seems almost certain that it will be a waste of your time and money: You're going to be surrounded by people who are not in your field and not at the top of their respective fields, so you're going to learn very little and you're not going to get very much credit for speaking there as well.