Why does my Anycubic Predator print backwards?
The right-hand coordinate system is the most used system on printers. So, when facing the front of the printer, the most common arrangement using a  is:

X+ will move the print head to the right
Y+ will move the print head away from you (towards the back of the printer)

For a Delta printer, when facing the printer, the Z pillar/tower should be at the back, the X tower on the left and the Y tower on the right. Do note that these tower are not corresponding to the axes movement, but are simply named as such so that you can use the designated stepper axes as indicated on your controller board. If you position the printer this way you have access between the X and Y pillars.
If the prints are mirrored in X direction, you need to swap X and Y steppers. X is the left column, Y the right.