Even if FQY perfectly master DG9S and DG9S > Sunflower Manual/Bixie Sword as JY said I highly doubt he can caught up with DFBB demonic speed and superior inner strength (since even when dying he/she can blind RWX eye) so in terms of martial art skill it's might be DG9S better than Sunflower/Bixie Sword but as a martial art master and fighter DFBB much more better than FQY..