For the purpose of identifying [possible] bot-generated usernames.
Suppose you have a username like \"bilbomoothof\" .. it may be nonsense, but it still contains pro
You could use a neural network to evaluate whether the nickname looks like a natural-language nickname.
Assemble two data-sets: one of valid nicknames, and one of bogus-generated ones. Train a simple back-progating single hidden layer neural network with the character values as inputs. The neural network will learn to discriminate between strings like "zrgssgbt" and "zargbyt", since the latter has consonants and vowels intermingled .
It is important to use real-world examples to get a good discriminator.