Felicia Moveset

tbh 37 spd is not that good for doubling anymore.
it's good for denying double, but felicia wont 1 shot anything with 40 atk with atk boon anyway, i think you better up still with +spd.

you can go for fury desperation and atk/spd ploy.
she has problem with defensive ploy, since her plate is an adaptive damage.
but I believe giving her ploy on her C slot is already enough, I would give her brazen on seal for her damage.

I replied to your previous question recommending +atk over +spd, and I haven't changed my opinion. I currently have Felicia now at +7 with +spd -def; trying this IV out to see if I like it better than neutral.

Vergessen is a very intelligent player so I don't quickly discount what he says. However, from experience I can disagree with his final conclusions.
- Yes, 41 spd at max merge isn't all that fast by today's standards, but we haven't considered an A-skill and there's still spd ploy, which I do recommend because mages get pretty fast. Just fury and spd ploy get her to 49 virtual spd, and we can still add ally support and potentially a buff. So even stuff like fury Nino+10 with the usual +spd might get natural-doubled.
- If you want to be very sure of doubling an enemy mage, use QR.
- He is also correct that dragons and armours with mixed bulk tend to cause her issues. If you want to play aggressively against this type, I recommend res ploy. Most of them have higher def than res (as do most non-mages, and most units without higher def she can hit pretty hard regardless). You will still see stuff that just has too much HP, but with the ploy she has virtually 49 atk, and then add the A-skill, ally support, and a buff (which I would consider necessary) and you should be at 56+ against their lower defensive stat so you're doing decently.
- He is correct in that she doesn't take counterattacks well, but at max merge she generally has just enough bulk to take one hit, especially if you use fury, because she's gaining both def and HP with merges. (Atk ploy can be considered, but I already recommended spd and res ploy. Atk ploy instead of spd ploy if you want to focus yourself against DC units, but your entire team will have a harder time against fast units.) After one counterattack she drops into desperation.
- I repeat: from experience, I have missed more than a few kills, especially in PvE, by 2-8 damage. 8 damage is too much for just an atk boon to cover, but I still had at least 2 atk to gain from merges at the time. Marth's Falchion buff was usually around.

Other points:
- avoiding fury is not a bad idea. I use fury and the recoil does add up in reinforcement maps. Her res gets so high I can sometimes get away with it, but sometimes Marth is giving her HP so she can fight on.
- Fortress def/res I do not recommend. She needs atk and spd, and this skill doesn't help.

Here is my Felicia project. +Spd/-HP.

I think Speed should be a priority. If you refine her plate weapon to take advantage of adaptive damage Attack is important, but not as much as you'd think. I like the plate weapon effect...bait a mage, then counter attack...on second counter attack trigger special = dead attacking mage. Fury/Desperation/Brazen seal is lethal. I have Def Ploy...which I think is the best ploy for her to use. I get trying to use DD A slot, but I feel like she is really built for Fury. Speed is everything for her imo.

Her Res is so high she can tank vs. mages. Her speed is so high she'll only get hit once and she can typically survive a single hit from a ranged dagger/bow (or counter from Black Knight). Once she hits desperation range she nukes pretty much everything except balanced dragons. Honestly, she's a lot of fun to use.