Which Effie should I promote? Please help

People might disagree with me but I'd prefer to run neutral on her instead of having more attack to worsen her below-average defense (For an armor knight) since her massive attack is already very high and not super mandatory to raise in order to sacrifice for defense.

Imo you should promote the neutral IV Effie.

If you are running vantage, I prefer + attack even with Def minus, also with brave build. Any other build I'd prefer Def + and minus speed.

Of course I prefer +atrack and minus speed the most if I had a choice. For me, if she's in armor emblem, the Def is not a big issue bUT higher attack helps you kill off some greens as well. Because she has pretty solid hp as well, a loss in Def is not too bad if you running armor or have other off setting buffs. It also depends if you are running distant counter or not.

My effie is actually the + attack and - def with distant counter and wary fighter. Had I gone vantage, then it wouldn't really matter, but since I don't and I'm running killer Lance, I need to get a +def -speed one.