Use custom domain without transfering domain hosting?

Hello,

I have a question related to domains and emails.

I am member of a local sport club that has its own domain (domain, website, emails).

I have an email address myname@mysportclub.org that is currently an alias forwarding emails to my runbox address.
For receiving: it works perfectly.

for sending, different story : I just tried to create an identity in my android email client for this. It half works:

I was wondering if I can do something to make it work, without disturbing other email user of this domain, to send from this alias address through runbox (both on webmail and smtp),

Hello. It might actually be better if you contact us at support@runbox.com so we can look at your exactly set up on a per account basis.

To send email from an address that isn’t hosted by us you would need to create an Identity in your Runbox account otherwise our servers will not let you send email from that domain.

In addition, as you say you will need to modify the SPF record for your domain to also include the Runbox SPF record which is explained at the link below:

Runbox Sender Policy Framework settings | Runbox Help

DKIM signing is not possible unless the domain’s email is hosted by us under Email Hosting in your account rather than it just forwarding email to your Runbox account.

Forwarding email is becoming more tricky these days because with the increase in domain security it requires more setting up and more features at the email provider side and such features are not necessarily in great demand.

I hope the above helps in some way.