changing image of posting user without webhook or alternatives that convey the same thing

I have a bot that I use to forward messages from github to discord (and vice versa but not relevant here) and im currently using embedes to show the messages like shown in the picture, which I think look great and is very pretty. That being said ive had a few users complain that the embedes dont seem like regular messages because they are not on the same indentation as the regular messages and that it cuts the flow of reading a thread. To fix that my thought was to just post on root but that is only possible with webhooks as far as i can see? Assuming I want to play with the name and icon that is. So I'm asking an open ish question becauase I dont think there is actually a way to do this with a regular message so any suggestion on the matter would help me as there might be some discord elements that im not aware of that i can use here. on the github side i can render some html in the github flavored markdown so thats how i do user images which i dont think i can do here