Hi, there!
Devblog post with characteristics is here: https://blog.worldofwarships.com/blog/273
At each ship's max range:
T8 Cherbourg: Maximum dispersion - 197 м. Sigma – 1.80 (17.7km)
T9 Brest: Maximum dispersion - 201 м. Sigma – 1.80 (18.2km)
T10 Marseille: Maximum dispersion - 213 м. Sigma – 1.80 (19.6km)
Compare to: (at 18km - max range on Dunk, the Max dispersion gets higher the farther the range)
T6 Dunkerque: Maximum dispersion - 242 м. Sigma – 1.70
T7 Strasbourg: Maximum dispersion - 242 м. Sigma – 1.80
T8 Richelieu: Maximum dispersion - 242 м. Sigma – 1.80
T9 Jean Bart: Maximum dispersion - 242 м. Sigma – 1.80
Compare to: (at 18km - slightly above max range on Charles, but dispersion get higher as range increases)
T8 Charles Martel: Maximum dispersion - 157 м. Sigma – 2.00
T9 Saint Louis: Maximum dispersion - 157 м. Sigma – 2.05
T10 Henri IV: Maximum dispersion - 157м. Sigma – 2.05
According to the numbers, these new cruisers function as "battlecruisers" - meaning their dispersion is between Cruiser and Battleship levels, but Sigma is Battleship level due to the BB caliber to the guns.
The person on stream was likely the EU rep - so "accuracy" may not have been the word he was looking for. Cross-language gets more difficult the more specific we need to be.
Id' cut him some slack