This is my host and the source of the connection info I use: https://support.bell.ca/internet/email/how-to-use-bell-mail?step=5
(That is what you find when you search for smtphm. The .co.jp-part doesn't really anonymise it. You should have used the original from the get go.)
I get local "daily output" emails from "r...@local.home" sent to "r...@local.home".
Do you have root: wt...@bell.net in /etc/mail/aliases?
Note: the domain is "local.home" and not "local.home.org" which is what it is when I try to send to external addresses.
Not sure if I understand you there. My last guess: action "relay" relay \ host smtp+tls://my_re...@smtphm.sympatico.ca:587 \ mail-from wt...@bell.net \ auth <secrets> -- You received this mail because you are subscribed to firstname.lastname@example.org To unsubscribe, send a mail to: misc+unsubscr...@opensmtpd.org