ENTP is not ENTj. We already have an ENTj here who also posts on a socionics board (FDG) who will confirm to you he's ENTJ in both systems. We have Z who's INTJ and INTp there as well.
The easiest way to go about it though is quadra values. Gamma NTs like discussing ideas like an ENTP might, but they have a heavier interest in terms of practical, political, or monetary concerns. They're called "light researchers" in Socionics, while ENTps are heavy researchers, and part of the Alpha segment of NTs who enjoy theory and Ne ideas just for the fun of it. Ni Te Se Fi (all Gamma values) is more goal driven, just like MBTI NTJs.
Gamma types like to talk about where present trends are leading in terms of potentially profitable events and undertakings.
Gamma types tend to give more value to ideas and concepts that are firmly connected to factual information
Alpha types are inclined to discuss highly theoretical concepts as a source of intellectual stimulation and fun rather than for their practical merits.
And they are generally not socialable in the same way as ENTP.
Groups made up of primarily Gamma types tend to be small in size; perhaps 6 at most. Laughter and very obvious displays of emotion are subdued, instead, there is a lot of smiling, amusement with ironic and witty remarks or, when serious subjects or not very happy personal experiences are discussed, a serious demeanour. Even such small groups tend to split into smaller ones; perhaps 3 is the ideal "group" size for Gammas.
Group discussions are focused on exchange of information and ideas on subjects of mutual interest, discussing and planning activities together, or on personal experiences. The latter are usually discussed not with the purpose of making people laugh or to boast one's position but to get an insight into the lessons to be drawn from such experiences.
Gammas usually dislike being "drawn" into larger groups where loud exchanges of jokes and quick shifting of one subject to the other are the norm, as in a large dinner table in an informal environment, especially if the group is also somewhat "artificial" as in work colleagues or business partners where personal relationships weren't really spontaneously formed. In such situations, Gammas will tend to focus on the persons sitting immediately near them in order to engage them in more individual conversations or will tend to remain mostly silent, not really participating in the group atmosphere, making the impression of being "introverts" in the everyday meaning of the term.
Once a group is formed, it tends to be wary for some time of "newcomers", being neither exclusive nor inclusive on purpose. Conversations often focus on trends regarding material and yet personal issues, such as career prospects and developments, success or failure of financial investments and enterprises, and the future prospects of romantic relationships, as well as the reasons for the failure of past ones. In more light-hearted moments, such talks get a "bawdy" flavor with some slight teasing.
Other subjects tend to focus on internal work politics from the point of view of how it jeopardizes general efficiency, the nonsense of bureaucracy, and how to be better than competitors.