No those are two different things.
A manual submission on a .edu link means the poster writes a comment that is on topic that has a much higher chance of approval on a moderated .edu blog page that is not auto approve. The goal here is to get a high quality link that has low OBL etc.
The slow submission mode on scrapebox is meant to give a higher "submission" rate process on blogs that scrapebox fails to load during the fast poster. It is not the same as a "manual submission", but more of a technical fix.
They are two different things, do not confuse the two.