Does orbital rendezvous require six degrees of freedom?
Solution 1:
What you're looking for is called translation, and it is possible in KSP. But you'll need Reaction Control System enabled on your vessel to be able to do it.
You can use H, N, I, J, K, L (default keybindings) to perform short RCS thrusts in every direction. Or you could switch to docking mode (it's the small blue button in the bottom-left corner of the screen) and press the space bar to switch A, D, W, S between rotating the craft and translating it.