Windsweep

I've seen a dual L+D (with Baskillos) Windsweep build on Raven, and a +Spd refine on lightning or dark breath on Female Corrin has also worked. To see all the builds, just look at https://fireemblem.gamepress.gg/passive-skills/windsweep-3

Alm, in many cases, isn't the best use of Windsweep either.

Windsweep is good for units that you'd want to attack physical-attacking units, but don't want the hassle of dealing with things like Distant Counter, or just counter attacks in general. I find it better (along with its Water variant) on chip-damage, or buff/debuffer units. Their main thing isn't dealing damage (at least most of the time), but being able to debuff, and/or buff depending on the weapon, to give their allies and easier time dealing with the enemy.

Can't really do that job if they have to worry about people with Distant Counter. That's why I put Watersweep on my Sothe. Since most people use Lightning Breath, or some form of Distant Counter, on them, being able to attack them without fear of retaliation is sweet.

Well.... Joshua, because he can play ploy against dragons, Also counter of most dragons, If not all (blue dragons are slow ir have low atk)

Also Free damage without fire Sweep is nice.

But If you have a +spd eprhaim you can put darting blow and double everything with eff of fire Sweep lance, if refined His Siegmund. With brash Assault.

Windsweep can be used in many ways
On debuffing units, like windsweep Corrin or Dark Breath+ F!Grima (which I'm doing)
Countering DC for Ranged Units
Or for units like Elincia
Or just for some meme build

I have an actual example of an interesting windsweep use in my friends list. It's pretty much a follow-up to the buffer/debuffer examples that others gave here.

The unit is Fae (but I guess that all light/dark breath dragon variants can apply). She uses windsweep to trigger her light breath buff on player phase and then she benefits from the huge buff on enemy phase, where she just tanks everything (combined with DC A-skill).