Flour vs cornstarch for keeping fresh uncooked pasta from sticking together

Use bench (AP) flour for working with your dough. I will sometimes toss the freshly cut pasta with a bit of flour to keep it from sticking together, if my dough is too tacky. I typically use semolina to keep the freshly cut pasta from sticking to the plate that I place it on. I never use cornstarch for pasta. Your best bet is to roll into sheets. Dust those sheets with a bit of flour. Depending on the humidity level, I let them hang out on the counter for a bit to dry. Flip over once, you'll get the sense of how much flour is necessary to keep the sheets from sticking to your counter or board. Try to use as little as possible. The correct dough hydration is a bit tricky and will take some practice. After they air dry for about 10 minutes or so (this could be much shorter if it is very dry), cut your pasta. Toss with a bit of flour, and place on semolina sprinkled plate or tray. Once you fill the tray, freeze your fresh pasta (unless cooking immediately). Then cook from frozen. Go for it. Even if you make mistakes, it is edible! You will get better.

To answer the precise question as stated above: wheat flour will draw more moist and get stickier than for example corn starch (i guess, because of the gluten content). So depending on what kind of noodle you're making you have to judge what to use. There are pretty dry doughs for noodles (especially the italian dry variants) where you can easily get away with regular flour.

That said, in case you have a really sticky dough: rice flour draws the least amount of moist, as far as I experienced it. I use it to dust my banneton (proving basked for bread making) and the bread will come right out of it without sticking to the banneton. Maybe you could try that as well!

However regarding my own experience with noodles: My dad uses semolina to make his dried noodles (italian style tagliatelle without egg, so again: not entirely sure if relevant). Before cutting he dusts them heavily with semolina. If he thinks they might still be a bit too sticky the dusts them again after cutting and tosses them a bit. They can be cooked right away, but most of the time they are premade to be cooked later that day. My dad rolls them up into rough nests, so they don't take as much space. Also this way he can make a huge batch and use a portion right away while drying the rest for later use. They never stick to each other and cook perfectly.

I never dust it. Make dough that's pliable but not sticky, then either dry it on a rack or par-cook it https://www.youtube.com/watch?v=fgbrEOG_imw&t=8m41s