(1) ENTPs have Ne and ENFJs have Ni. So ENTPs tend to be more “all over the place” and do a little bit of this, a little bit of that, and then something completely different. What they’re interested in is whatever is new and expands the borders of their present understanding, breaks it down, and “allows them to see what they have never seen before”. In contrast, ENFJs use Ni, so while it is of course human to be scatterbrained to some degree, ENFJs will overall be more coherent and weave a single narrative about their person and purpose. That is one reason why ENFJs can frequently move men to get behind a cause (e.g. Martin Luther King, Jr.). ENTPs are typically more interested in pursuing their own intellectual interests, and talking about complex intellectual stuff is not a good way to mobilize people. As Newt Gingrich says: “I’m not a natural leader. I’m too intellectual; I’m too abstract; I think too much.” This goes for many an ENTP.
(2) Both ENFJs and ENTPs have Fe/Ti coupled with N, so they both have that mindset where they naturally look to other people to try and understand what is going on inside them, and they may even adapt themselves to others in order to make others feel good. So both ENFJs and ENTPs share this adaptation where on the one hand they please people, and on the other hand they find the whole situation slightly comical because they’re introspective enough to see how they’re sometimes just “going through the motions” without actually meaning all of the things they express to make others feel good.
ENTPs have more Ti, so they’re often more callous about it. They often state flatly, like Catherine the Great does, that people are dorks, predictable, boring, etc. – things that “one really shouldn’t say” for good Feeling.
ENFJs have more Fe, so they tend to be friendlier and more light-hearted about making fun of people. While ENFJs may also have feelings of disappointment about people in general, they would rarely state outright that people are dorks – from the Fe point of view, blaming people just undermines the potential to try and work with them.