Hi.
AFAIK, the modules responsible for the above error are: psaddonsconnect and (if excluding the first one doesn't solve the problem)- ps_mbo (both in /modules folder).
I'd suggest You making a copy of both modules, , delete each one, clearing the cache folder manually (var/cache) and you'll be able to login to the backoffice (unless there are further errors unrelated to the above issue).
This issue is addressed on GitHub:
Unable to generate a URL for the named route "admin_addons_login" #30979
Good luck...