I t does work for he Sony Next 7 , these three possible options.
Sony HVL-F20M External flash. This is an entry level but it does the work.I used for parties , very happy with this product. Rated 4 Starts.
Sony HVL-F60M External Flash, Rated 4 Starts.
Sony HVL-F43M External Flash. Rated with 5 Starts.