Nothing is mandatory on a CV. You could send an anonymous one too.

As for the photos, i am not sure how many CVs you see, but the ~100-200 I saw in tech across the last 5 years all had a picture (except a very few ones, which I noticed). I do not pay much attention to the picture because of experience (I am horribly bad on pictures, and some of the best people I worked with were extravagant), but this is me.

There is nothing legal or illegal there, just a matter of tradition and therefore not having one makes you stad out, not necessarily in a good way.