Error While building a custom build of unreal engine.

To me, this seems like a .DLL didn’t build correctly.

Part of me thinks you should delete the contents of the bin and intermediate folders and rebuild the whole project again.

However, take a look at this thread. Part of me thinks it is worth trying out some of the solutions that are less drastic: Plugin 'X' failed to load because module 'X' could not be loaded launch error - #10 by BDC_Patrick

Apologies for the late reply, for some reason I didn’t get a notification about the thread. Let me know if this solves it!