Match Two PCBs Layout and Dimension in EAGLE CAD
The easiest and safest approach here is to simply note down the X-Y coordinate and rotation of the two connectors in the first board, and then simply apply the same coordinates and rotation to the corresponding parts on the second board.

You can do this by right clicking on the components origin, selecting properties, and it will tell you the coordinates. In the second board you can do the same but type in (or paste in) the new coordinates for the connectors.



I would additionally recommend locking the parts on both boards once placed in the correct locations to prevent accidentally moving them later on in the design process.





A more advanced technique would be to open up the .brd files in a text editor (they are just XML files), and change the coordinates with a simple copy paste. Be sure to have a backup of your eagle files before attempting this approach just in case something goes wrong.

You simply have to search for

&lt;element name="CON1"


Or whatever the name is and you can change the x and y positions there. To change the rotation, either edit or add the rot="R##" attribute, where ## is the angle of rotation. For parts on the back of the opposite side of the board, this would be rot="MR##".

I would not recommend this for parts which have already been routed as this method will not move the routes. Additionally you'll need to run ratsnest once you reopen the board in eagle to update the airwires.

However this approach is quite useful for updating multiple parts quickly.