When holding down the Ctrl key and pressing another key, if there is an input event bound to that key, then the nodes placed after that input event are triggered. However, this is not the case with the E key. I tested multiple keys such as Q, W, R, T, F, and S and all of them behaved as expected even when the Ctrl key was pressed as well. I also tested the E key with the Alt key and it worked correctly, so it seems that the specific Ctrl + E combination doesn't work.
I also unbound Ctrl + E from the keyboard shortcuts and it still didn't work.
Tested in //UE4/Release-4.26 @ CL 15973114 and this did NOT occur so marking as a Regression
No input is detected
The text from the Print String node would be displayed on the viewport
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-135765 in the post.