How to draw out of XZ plane in Blender? I have started a new project in Blender and selected 2D animation mode.
Next I drew few shapes and then rotated scene a bit and found, that all my drawings were actually in 3D but constrained into $XZ$ plane with camera, looking at the plane.

What if I want to draw in other planes, say $XY$ or arbitrary plane, say another one parallel to $XZ$? Is it possible?
You have 2 options available in the viewport to control the placement of new strokes.
Hint : Hover your cursor over a setting to see more information about it.

Stroke Placement
You can choose to place the drawing plane on the World Origin at $(0, 0, 0)$, on the 3D cursor, a 3D mesh surface or another stroke.
Drawing Plane

You can Choose a plane orthogonal to the view, on the global XY, global YZ, or global XY plane or on the local XY plane of the 3D cursor.
By default the 3D cursor is not visible in the 3D viewport in 2D Animation. Enable it in the overlays :

To move or rotate the 3D cursor, you have to open the &quot;N&quot; panel with N, and go to View &gt; 3D Cursor Panel. You can also change the tool in the left hand side and move it with the mouse in Object mode.