Need help with scan-to-email function on printer

Yes. SmtpClientAuthenticationDisabled = False only enables SMTP AUTH; it does not necessarily allow Basic AUTH for SMTP.

The key thing to check is the Authentication Policy actually applied to the mailbox. Microsoft documents AllowBasicAuthSmtp separately.

Run:

Get-User email address removed for privacy reasons | Format-List AuthenticationPolicy

If a policy is returned:

Get-AuthenticationPolicy "PolicyName" |

Format-List Name,AllowBasicAuthSmtp

You need:

AllowBasicAuthSmtp : True

If there is no mailbox policy, also check the organization's default:

Get-OrganizationConfig |

Format-List DefaultAuthenticationPolicy

Then inspect that policy's AllowBasicAuthSmtp.

Important in your case

The fact that the server advertises:

250-AUTH LOGIN XOAUTH2

does not prove that Basic AUTH LOGIN is permitted for the account. Exchange can advertise the mechanism and subsequently reject the authentication attempt. Microsoft specifically notes that an authentication policy blocking Basic SMTP overrides the normal SMTP AUTH mailbox/tenant settings.

Also, app passwords won't bypass a Basic-Auth block; Microsoft explicitly says blocking Basic authentication also blocks app passwords.

One other major point: Microsoft has been retiring Basic authentication in Exchange Online, so for a Ricoh that only supports AUTH LOGIN, the long-term solution is likely SMTP relay / direct send / a modern-auth-capable firmware or intermediary, rather than continuing to troubleshoot mailbox-password authentication.