“is there a chiyuv for a family member to follow a family minhag shtus that goes against the shulchan aruch? maybe.”
APY,
The above minhag is stated in many poskim so its certainly legit and not a “shtus”. As for the Mechaber, he is generally speaking about the very Chiyuv, which means if there is no man around the Isha certainly has a chiyuv to light, it is no less then Kriyas haMegilah and is not excepted from Zman Gramah as per the Gemara as being part (or the main) of the ‘nes”.
Daas:
As for the Mishnah Berurah, I’m not so sure what the meaning is:
תרע”ה סק”ט: ועיין בתשובת עולת שמואל סימן ק”ה דלדידן שמדליקין כל אחד בפני עצמו מכל מקום אשה אינה צריכה להדליק דהויין רק טפילות לאנשים ואם רוצים להדליק מברכות דהוי כשאר מצוות עשה שהזמן גרמא דיכולות לברך
Is he speaking about a single girl? I assume it is pertaining to a married that is טפילות לאנשים. Otherwise, why is a single “טפילות “? Where do we find such a savara?
Or perhaps we say on the halacha of “mehadrin min haMehadrin to be Yotzei the shitas haRambam we don’t apply that ‘chumrah’ to women, and they can rely on the other shitos.