I transferred schools in my sophomore year (junior now), and my grades were admittedly better at my old school. But that’s mainly because the new one is harder (which I already know to mention in my application).
In terms of GPA though, would colleges care more about my GPA at the new school or my cumulative GPA for all three years? The one at my old school for two years is about 3.6 UW/3.9 W, and the one for all four years (at this point) would be 3.75 UW/4.23 W.