Idea of Reply All Arrow Icon
The image is a double arrow that's pointing to the left. One arrow covers most of the other one. The points of the arrows are straight to the left but the tail curves up from below then turns to the left.
This page contains the Reply All Arrow vector icon, as well as variations of this icon in different visual styles, and related icons. All icons are in the flat vector style, however, differ by the line thickness, fill, and corner radius.