No that is not possible.
You may however request a username change (must PM and ask an Administrator and fyi Paul M is currently away on vacation) to one that is completely "random" however before doing that we recommend you edit your settings and remove anything that would hint as to who you were previously.
Has this been asked and done before? Certainly but so you're aware we do not delete any accounts.
Edit: Also if this was related to
https://vborg.vbsupport.ru/showthread.php?t=310587 because one thought by deleting an account it would take place instantly and thereby require no username change and such then no that would not be the case due to the fact accounts are not deleted. I'm not saying you hinted at that or even mentioned that, it was pure speculation on my part.