The message , with the pictures remains in the out box. I have sent other messages, without pictures this morning.
You’re not being very clear. Do you wish to add an image to a message you want to forward, or is the image in the original mail that your want to forward?
By default, eM Client forward or reply with image that are in the original e-mail, even if the image is blocked (by unsafe content setting). You just need to be online when forwarding/replying.