Yes, you can have a left-handed interface in Concepts. In fact, you can customize every part of your workspace. To rearrange the menus on your canvas, simply tap+hold+drag any menu tab or the outer ring of the tool wheel and move it to a better location.
If you’d like to see this in action, you can watch a Getting Started video.
For Windows: https://www.youtube.com/watch?v=HVrnAdnxdis&t=358s
For Android: https://www.youtube.com/watch?v=2udMhtsUbiU&t=3s