@Billsh Yes you can cut the branch, above or below the junction, depending on the length that you would prefer. You can remove the leaves; wait a couple weeks for the cut end to callous before planting.
However, since you are in OH and your plumeria might be entering the dormancy period now, there is a higher likelihood that they will not root easily. It is best to take the cuttings and root them in spring. You might even get your rooted cutting a chance to bloom.
