SQLDeveloper has an utility to export the short-cuts. It is an excellent way to ensure that short-cuts, are kept uniform, can be shared across the team. I have listed below steps to export the preferences and import them back.
1) Navigation: Tools-->Preferences (Screen -1)
2) Select Shortcut Keys (Screen -2)
3) Click on More Actions and select Export in the drop-down list (Screen -3)
4) Select the directory to save the file (Screen -4)
5) Importing the preferences is similar; follow the steps 1 & 2 and in step 3, select "Import" instead of "Export" and select file to import. (screen -5)
6). An confirmation window will appear (Screen -6), click on "yes" and the Short-cut preferences will be imported.