None of those subjects will affect your application for engineering if it’s general engineering or mechanical expect chemical engineering which requires chemistry.
Tbh this was really long to read but basically choose you like to do. You need 3 but if you want to do 4, do it on something you like and your plan of what to do with that 4th is good in case you like it or not. If you’re more concerned about your social life in school, don’t worry about not having any friends in school because you’re bound to find someone who will first to introduce themselves and you can always have someone to talk about within your subjects.
Even though sociology isn’t relevant to engineering you could always link what skills you learnt in your personal statement to show what you have as a student. The others that say a uni will do not care about the 4th subject as long it’s a good grade I agree because they’ll make an offer with what your current predicted grades was.