I think English is reasonable because it gets its post-Roman status by being descended from (Norman) French.

I agree that Anglo-Saxon is a bit more tenuous - my thinking here was that they are vaguely related to the inhabitants of Britannia during the time of the Roman invasion... but, actually, on reflection, I'm not very sold on that. (The Angles and Saxons were German/Danish invaders. They probably intermarried with the locals... but still... tenuous...)

Breton is a good call though. I'll add it.

I would say you should replace English and Anglo-Saxons being able to do it with Breton, given they're descended from Roman-ruled (and possibly Romanized) Britons and the Anglo-Saxons had minimal influence from the Romano-British they conquered.