I have tried to add a datetime to a datetime, it is not working as well. The convert pin menu is not opening for the input pins. If you add another input pin, there will be a datetime, a timespan and another datetime pin created, which can be connected to two datetimes. But shows error on compile.
UE5 Preview2
P.S: Today I compiled an Editor from 5.0 branch, the problems still exist.
Still happening in UE 5.2.1 I found some doc page from UE 4.27 and it seems that there was a DateTime + Timespan node allowing you to add a timespan on top of a datetime (which sounds logical, as timespans not being able to offset datetimes are pretty useless by their own), but apparently that node is nowhere to be found in UE5 docs…
Still a problem for me in 5.3.2. Dustini’s advice didn’t help me I’m afraid.
Edit: Found a workaround by converting everything to seconds and adding it up. Here’s how it looks if it helps anyone