I use Business Calendar Pro. I press and hold an event in Agenda view to copy the event. I then change the date of the copied event to reflect the day it will take place. I can also adjust the time and additional info if needed.
Creating a repeat event then editing the second one is a workaround NOT a solution. Not having the basic functionality of copying a calendar event to another day is just unacceptable! Can't believe this feature was removed. My old S4 was able to do it.