Does “impeccable flow” sounds unnatural or weird to you?

What makes it sound wrong to you?

Impeccable: adjective (of behavior, performance, or appearance) in accordance with the highest standards of propriety; faultless. You can use impeccable to describe something you think is done incredibly well or without fault!

Impeccable flow is how I would describe any rapper with a smooth delivery and clever witticism. It's not just natural, it's the ideal phrase for the situation, in my opinion.

It's fine.

Impeccable flow sounds perfectly fine. I've used that phrase to describe many rappers.

I wouldn’t use it this way. Its root meaning is something like “not capable of sin” and was in the past ordinarily applied to persons. It’s become a lot looser now though so this usage is not wrong per se.

Flow is probably the strange word since it has a different application in rap. It's often used to describe a cadence and rhythm that match together with the music to "flow" effortlessly and not clash with the music. A particular good flow will include some complicated rhythm and maybe some syncopation and other things that feels like it shouldn't work but the artists seems to glide over the beat

Not only does this sound fine, I'm pretty sure I've heard this exact phrase in this context multiple times.

I can think of two places I'd consider "impeccable flow" to be perfectly natural: Music and fluid dynamics

Kind of has a slightly humorous edge to me because the word is a bit formal but it absolutely sounds natural, especially in a colloquial context. "Bro's flow is so immaculate, it's atrocious."

Impeccable flow - a flow free of errors, flaws, stutters or stammers. So yes by English's weird "rules" it works just fine. However it should be used to describe a live performance not a recording. The live concert was impeccable but the CD is perfection with no room for errors so it's kind of redundant to call something filtered to perfection, perfect or impeccable.

I’m with you: impeccable means “without fault”. Music is subjective by nature; flow is neither “right” nor “wrong”. It can be “good” or “bad”, though.

Impeccable flow is used so often when describing a rap artist, that its kind of overplayed at this point.

Not at all, it's an impeccable phrase

Impeccable is a five dollar word. It isn't out of place there, it's just that it's not a super common word to use in any circumstance.

Impeccable is a fine word to describe that. Absolutely.

Only in that the stereotype of a rap afficionado is not that of someone who would use a word like "impeccable" (or afficionado for that matter). But stereotypes are invidious.

Maybe they see the word as "too formal" for a casual conversation, but there's nothing unnatural about your usage of the word at all

*sound, not “sounds”