Text scrolls or rolls

When creating an ending credit scroll or roll, does Resolve 20 or Fusion 20 use Pixel or Subpixel settings?

If you're talking about the premade effect accessible in the Edit page, I'm not sure what it uses.

If you make your own with Transform node it's always subpixel, but you can constrain translation to integers by keyframing two integer values and extrapolating the rest of the curve. There is also a very useful option at the bottom of Transform's panel called "Reference Size." If you check it the Transform's XY coordinates switch from normalized values to pixel counts.