It’s possible to flip an image on your canvas by using Free Transform in order to rotate it. Just press on the middle square on the side or top of your image, then drag it to the other side!
How do you flip things in Medibang?
2Rotate Canvas (Flip)
When you would like to rotate or flip the entire canvas but not layers, go to the menu and click ‘Edit’ and select the direction you want to rotate in. The canvas will rotate 90 degrees in the direction you choose.
Where is the curve tool in MediBang?
Mediban Paint has a Tone Curve in the menu Filter. When selected, a new Tone Curve window will appear.