Images with transperencies and placed in formular fields are separeted wrong when exported as PDF.
PNGs and PSDs with transparency and directly imported in an InDesign formular field are separeted wrong when exported as a PDF and separeted to cmyk. The images are too dark with a green tone.
This happens in the last InDesign versions til the last CC2019 (14.01).
Mac OS 10.14.3 and also in El Capitan