-Atk +HP Lene’s Potential?

She's a dancer first and a fighter second, and even then her main shtick is arguably defense due to her sword, Safeguard, being an enemy phase weapon.

There are a few different ways you can build her.

This is a set that I'd probably run on her if I had your IVs. While it may not be the most optimal for her, she can be pretty fun. Being able to buff attack, speed, AND defense while dancing for support, and then being able to take a hit thanks to Safeguard, seems like a fun build to me.

Of course, you can always fodder her off for her Safeguard+ since she's a 5* exclusive. It's certainly an interesting weapon for units like Selena/Laslow/Hinata/Arden/etc.

I mean all dancers are viable and they rarely fight by themselves. If you need a red dancer, you could go for the more accessible Olivia and fodder off Safeguard for a project, but as I mentioned, she's mainly serving just as a dancer. She'll do fine enough with Wings of Mercy on B, then safeguard allowing her to tank a few melee.