PA! azura

It's possible to turn singers/dancers combat-capable. But IMO that's not really their function. They're supposed to focus on supporting their teammates, not stay on the front lines. I think you should just focus on giving her a support build for consistency.
However, you can be creative and give her something like Slaying Axe+ (+Spd), DC, and Wings of Mercy. I dunno, just a suggestion.

The way I always say, for Dancer/singers you mainly want to have a -atk to focus more on their survivability over anything else since they normally don't see combat in the first place

My PA! Azura is +Atk - Res... she would be a great blue mage baiter with +Res, not to mention she comes with TA. I'd say if you wanna give her a shot on the battlefield, her Prf weapon is perfect considering it gives a "Fury effect" with no downside with regard to buffs.

(Also, ignore her Geyser Dance... I dun goofed lol)

The -spd bane hurts but it doesnt take away from her main role which is support, just slap wings of mercy on and use her base kit. Iceberg is also a good special with the +res