I remapped ctrl to alt and alt to ctrl on my main system via the keyboard settings on KDE; but, RDP refuses to respect that decision. I did figure out a way to do this on Remmina; but, was wondering whether there is a way to do this on KRDC, since I wish to go with KDE apps wherever possible.
I don’t know of any way to do that directly in KRDC now. Earlier versions had the option to pass arguments to the backend, which would have made this possible, but thats gone now 
The KDE Settings changes key events on a layout basis, but RDP-Clients transmit the lower level keycodes, so you could instead remap them at that level using software like xremap, input-remapper, inputmangler, evsieve, … .
I am on a Atomic Distro so it would be great if the solution involved me not layering packages into the base system (or at least have a gui backend??)
Right now, only input-remapper has a released gui.