This is a scene in my crossover where Admiral Sunset Shimmer awaits for Rainbow Dash to a secret meeting where she plans on using the magic invested within her Admiral powers to transform Rainbow Dash into an Admiral as well.
Note: The white flag doesn’t necessarily mean “surrender”. It’s more a sign wishing to talk.
Crossover background:
This comes about a year after Line Ark overthrows Luna and Celestia and takes control of Canterlot. Her intention is that she gives Rainbow Dash the power of an Admiral in exchange for declaring war on Line Ark, while Sunset Shimmer executes a coup on the Line Ark Counsel while they are distracted in an attempt to make herself absolute ruler of Equestria and in turn, crush Rainbow’s rebellion.
What ends up happening is that Shimmer’s coup backfires as a magicless alicorn (Red Cap) finds out and warns a new unicorn who recently joined Line Ark (Trixie). Together the two managed to thwart Shimmer’s Coup forcing her and her fleet to run. In essence, this gives, the now Admiral, Rainbow Dash a much easier task to take back Canterlot from a now divided Line Ark.
More info on Admiral Shimmer can be found here: