Instead of temporary, try a mail forwarder like SimpleLogin or something similar.

Have you considered just buying a domain to use as a catchall address. That's what I use for the small % of services that refuse my simplelogin emails.

It's a cat and mouse game, since spammers will leverage this to work around bans or having to subscribe with phone or SMS verification on the major email providers.

These providers often end up on list such as https://github.com/disposable-email-domains/disposable-email-domains

You're trying to bypass an anti spam filter. If there was a consistent way to do that, spammers would exploit it til the vulnerability was mitigated.

I've been using fastmail and it works, but it's on the expensive side, enough to be unattractive to spammers. So that's one approach.