This test piece has 2 inclined surfaces along X and Y axis. And vertical surfaces on both of those axis too.

***Case A:

If your print has artifacts on; (like 'X' shaped crossed lines)
+inclined surface along X axis, check your Y-axis pulleys and idlers.

AND ALSO

If your print has consistent vertical banding on;

• vertical surface along Y axis, check your Y-axis pulleys and idlers.

***Case B:

If your print has artifacts on; (like 'X' shaped crossed lines)
+inclined surface along Y axis, check your X-axis pulleys and idlers.

AND ALSO

If your print has consistent vertical banding on;

• vertical surface along X axis, check your X-axis pulleys and idlers.

Note: Advices based on assumption that everything else set and calibrated correctly.