Is it possible like the fallout games to be able to win by using high conversation, stealth, etc?
Well, first option is to go with high INTELIGENCE (also skillwise if you want to get those extra dialog options, which appears when you have high "x" skill, PERSONALITY (people share more info and are keen to talk which is not always the case)... and ATTENTION, to notice small facial expressions, scratched floors, to feel airflow, hear sounds...
Second, quasi-pacifist (non-killing to be more specific) is to go with high STRENGHT and DEXTERITY, which allows you to intimidate, scare, and outmanouver opponents and NPCs istead of killing them or paying them. ATTENTION is also very wellcome here, but I didn't test it myself (I do currently the second, suggested by me, option with high ENDURANCE and melee/martial arts).
Pro-tip here: Some boosters (stuff temporary increasing stats/skills/resistance) will have their effect doubled when used twice (not more). It's very helpful with Rad-X, but also with... perfumes or joint :)