Anne has a gigantic scaling chain, let me explain.
So, before someone becomes a Knight, they have to go through Knight training. But to be even considered for the training, you have to prove yourself. You had to be the greatest combatant of your homeplanet. Knight Trainees are the greatest warriors from their respective home world across the universe. After becoming a Knight Trainee they will be trained by veteran Knights until they reach Knighthood after years of training. Oh and you only finish your training after being deployed on an actual battlefield once. They dying rate is pretty high, at least the half of all Knight Trainees died on Anne's and Pray's graduation. And only the half because they were saved all by them.
Knights are deployed an massive battlefields against aliens called AG's. Assholes that fire lazers and rush at you in masses, on ground and in air. A single mistake spells certain doom even for a veteran knight. suffice to say that a Knight that survives one of those wars is already worth his salt.
Then there are Master Knights. Knights who proved themself after countless wars. They are deployed like secret weapons. But even they get fodderized in case of a Type Zero
Type Zero's are high level AG's known and feared for being a massive turnaround on planetary scaled wars. A single Type Zero is enough for the Knight Order to sent groups of Master Knights after them. Blue Ring, a weak C, maybe even D rank, destroyed multiple ship fleets, killed 5 from a 21 man big group of Knights, the rest were seriously wounded, to the point that they were considered casuality. It took a Master Knight directly trained under Anne to kill it.
A case for a stronger Type Zeroes would be the Cross Eyes. On the Velchees war, that spanned 5 planets, they single handily killed a third of the entire human force. Knights and Master Knights alike died like flies facing them, to the point that humanity saw no hope in surviving. Anne and Pray were send to face them off in a duel. Fighting against an enemy that was clearly superior in strentgh, skill and experience. They won the all out duel in the end.
Pray was greatest Knight in humanitys history with Anne as the second greatest/greatest after Pray's downfall. In a verse where people can raze down entire enemy fleets with their powers, shrug off getting their body blown off or just being just superhuman in the first place. Anne and Pray are average at best physically. They dont compare to the biological super weapons created in the early beginning through family clans, splicing their genes to the point of being barely human. And they were still considered the greatest throughout the history of humanity. Their skill was that great.