I am afraid you are stuck with Elements default settings.
For special dimensions you need a more sophisticated editing program.
You need to capture in 1920x1080 which matches the preset.
I completely agree with Ann. PrE is designed to only work with standard video camera Frame Sizes.
Premiere Pro (about 6x the cost of PrE) CAN work with Custom Frame Sizes.
Now, if one does not need every pixel in the vertical, i.e. 1080 vs 1200, then the 1920 x 1080 Frame Size will naturally, effectively crop off the extras. Initially, that effective cropping will be both top & bottom. One can adjust the Fixed Effect>Motion>Position, to effectively crop from one, or the other.