As others have said it is legal. At only 10" overhang I would not even bother to flag it. If anyone driving runs into them they were going to hit your trailer anyway. I would paint the tips bright orange or something so people walking around the trailer don't walk into them.
Kubota MX4800 with BH-90X hoe; Hustler FastTrack 48; B3300SU (sold); 1969 Case 680B CK (sold)
Now you're getting creative. I like it. Traffic cones? Perhaps I could paint a couple of small children bright orange? I bet they could hold on pretty tight!