No, we can’t. See more information at https://gsuitelegacy.com/index.php?rp=/announcements/5/change-the-primary-domain-for-g-suite-legacy-account-no-longer-to-working.html
It will be added as the secondary domain.
You will be asked for a domain name you wish to use as secondary domain upon ordering. We will then set up that domain as the secondary domain of the account for you. We will also tell you the primary domain name and you will need to register or transfer this domain to keep your full control right. (You can register the original/primary domain with any Domain Registrar likes Godaddy, Namecheap, Name.com …