Some conferences I've attended provide stickers to put on your badge and if you don't want to be photographed/published the conference organizers may pay attention with respect to their publicity photos. Of course, others snapping pics with their cell phones may not. (And, in Germany as well as other countries, I've never seen explicit warnings about not publishing photos of people at a conference without permission.).

Most people are pretty reasonable and aren't aggressive with their picture taking. But there are almost certainly photos of you online whatever the local country laws may say.

In my country is like this, or was, I have not worked in that space for a long time.

An individual can record you on the street without problems.

A crew can't record you on the street for anything that will be aired on tv/cinema without your signing that you give your permision.

A Youtuber can record you on the street without problems.