Flipping horizontally and vertically in a PCB does not make sense if you have anything more complex than through hole transistors on it. If you flip things like an 8 pin opamp or a SOT-23 package then the PCB pads end up in the wrong places compared to the physical package. You can swap everything from top to bottom layer and vice versa because the pinout is preserved.

I know that component footprints will be reversed. I want to mount a raspberry pi onto a pcb upside down so the pins point towards the pcb. But all the drawings have the pi zero right side up so I just wanted to flip it. I I put it on the underside the silkscreen markings will also be on the wrong side.

If I understand correctly you want the pin order as if the board is mounted on the underside of the board (bottom layer) but the silkscreen in the normal orientation as when the board is mounted on the top side of the board (on the top layer)? A sketch is needed to clarify. In the meanwhile, please read: [https://easyeda.com/forum/topic/Arduino-MEGA-Shield-Project-703d187346e74833af8114b2f6aa423e](https://easyeda.com/forum/topic/Arduino-MEGA-Shield-Project-703d187346e74833af8114b2f6aa423e) The process that I described in this post: [https://easyeda.com/forum/topic/Is-there-any-way-of-mirroring-a-PCB-module-6a02dde9bbe74baf84e5fb363a85d749](https://easyeda.com/forum/topic/Is-there-any-way-of-mirroring-a-PCB-module-6a02dde9bbe74baf84e5fb363a85d749) might be adapted to help you solve your problem.

More topics to read that might help: [https://easyeda.com/forum/topic/Is-there-any-way-of-mirroring-a-PCB-module-6a02dde9bbe74baf84e5fb363a85d749](https://easyeda.com/forum/topic/Is-there-any-way-of-mirroring-a-PCB-module-6a02dde9bbe74baf84e5fb363a85d749) [https://easyeda.com/forum/topic/How-do-I-leave-the-labels-but-remove-the-parts-53430c692d204cb9be915c4d095988ec](https://easyeda.com/forum/topic/How-do-I-leave-the-labels-but-remove-the-parts-53430c692d204cb9be915c4d095988ec) [https://easyeda.com/forum/topic/Annotate-symbol-to-show-that-the-footprint-requires-placement-of-more-than-one-physical-component-deae7486f93d46028e05313e7874e4c3](https://easyeda.com/forum/topic/Annotate-symbol-to-show-that-the-footprint-requires-placement-of-more-than-one-physical-component-deae7486f93d46028e05313e7874e4c3) [https://easyeda.com/forum/topic/Placing-Arduino-Uno-board-on-PCB-and-schematic-e150516123994ca38cc9c1caf7469e80](https://easyeda.com/forum/topic/Placing-Arduino-Uno-board-on-PCB-and-schematic-e150516123994ca38cc9c1caf7469e80)