Need help identifying part: 2019 Prius Front Driver undercarriage panel

Well, the part you outlined is part of the front wheel fender liner - but it looks like your missing the piece next to it. According to your picture. Here's the amazon part number for the driver's side wheel well liner (T01248237). If your looking for the other plastic liner piece; Take your picture to the Toyota dealership parts counter to get a part number and estimated cost. Once you've got the part number, you can comparison shop - online.

Good Luck...

 

See catalog Figure 51-02, Suspension Crossmember & Under Cover, and Figure 53-02, Hood & Front Fender. Be sure to click View More Images to see all the illustrations.

 

That’s a 3rd gen in the pic, but probably very similar.

 

Shoot I was just underneath my wife's 2017, I could've checked for you....I've noticed almost everything has the part number right on it...you just have to search for it...pretty handy!!
If you can't find it, let me know, I'm getting my Prius up soon to install some mud flaps. (Was going to be today but it's just too stinking hot in this Colorado heat wave....can't wait for the 70's to return!)