DrColorChip is the way I would go. You can buff it first to get rid of the edges then do the paint touchup. Did it on my Si, can only notice it if you know where to look
I was searching for something for my 2020 Si Sedan. Ran across this website. Says it is for the Type R. but I think it would work on mine. I sent them a message to see what they have to say.
https://bigmikesperformanceparts.com/2017-2019-honda-civic-type-r-sns143/
I was looking at the HFP Side Skirts and don't see a big difference from what is already on my Si. Am I missing something completely? Or is a subtle change?