We have a report in Blogger Help Forum: Get Help with an Issue.
I use Scribefire to post to my blogs. It works fine with WordPress, but I have not been able to set it up with my Blogger Blog.And later,
I have already enabled the "Less secure apps" option. Still no go.This blog owner is patiently trying to diagnose a problem, over which neither he nor we have any control.
Apparently, the "Less secure apps" option only works for apps which have been updated to OAuth 2.0, for client login.
The "Less secure apps" option, in Google Accounts, simply appears to complement the use of OAuth 2.0. That option was provided, with an emergency upgrade to Microsoft Windows Live Writer, made jointly by Blogger and Microsoft engineers, last month.
Apps which have not been updated, to support the Blogger upgrade to OAuth 2.0, won't work - apparently even with a blog owner using "Less secure apps".
The ScribFire website appears to have been last updated a year ago - so the app may or may not be actively supported. The Home page does provide a possibly useful link.
If you are a ScribFire to Blogger user, you should try the link, and see if you get results. Otherwise, you may have to find another way to use Blogger.