Nice drawing. I don't see why it wouldn't work. On the 240g tank I was setting up awhile back, I decided to use 2 separate pumps instead of one like you show. I just had two bulkheads on the sump at the return area to feed the main return pump and the skimmer feed pump. I decided to do that so I could keep the return flow to the tank stable if I decided to boost/reduce the feed supply to the skimmer. On the skimmer feed pump, I put a tee and valves with one line feeding the skimmer and the other line draining back into the sump. That way if I wanted to reduce the pressure going to the skimmer I could just drain the excess flow back to the sump without having to put back pressure on the pump. Hope that makes sense! lol

Make sure you put valves with unions on the input and at the output of the return pump. This will make it much easier to remove the pump for cleaning and to replace it if needed. Many of the tanks I have seen and even setup myself were missing that and it becomes a pain in the arse to work on the pump if needed.