Email Source: Mail Ru Group

Homepage: https://mail.ru/

This source is known to forward email

Capable of generating DMARC compliant email for others

Yes

DMARC compliance via SPF and DKIM. https://help.mail.ru/enpostmaster/technical-settings/notes

Capable of signing email with DKIM for others

Yes

To configure DKIM, see the article: https://help.mail.ru/enpostmaster/technical-settings/notes

Capable of sending SPF compliant email for others

Yes

Contact Mail.RU support for SPF assistance.