Create Sharepoint Site via REST API with multiple owners - sharepoint

Question

So, I have a Power Automate Flow, which creates a Sharepoint Site using the Sharepoint REST API via "Send HTTP Request to Sharepoint" connector. I`ve following body:
{
"request": {
"Title": "#{variables('strSPName')}",
"Url":"#{variables('strSPAddress')}",
"Lcid": 1031,
"ShareByEmailEnabled":true,
"Description":"-",
"WebTemplate":"SITEPAGEPUBLISHING#0",
"SiteDesignId":"-",
"Owner": "#{outputs('Get_my_profile_(V2)')?['body/mail']}"
}
}
So right now I have only me as owner, but I need an additional owner.
I`ve tried to set two owners in an array like this:
"Owner": ["#{outputs('Get_my_profile_(V2)')?['body/mail']}", "email#test.com"]
Unfortunately, I`m getting the following error:
An unexpected 'StartArray' node was found when reading from the JSON reader. A 'PrimitiveValue' node was expected.
Any suggestions?
Thanks in advance.

Answer 1

As far as I am aware you can only set one owner when creating a site via the SPSiteManager endpoint. However, a workaround could be to add the second user to the Owners group directly after creation with a second POST request.
Below is an example
The principal id of the sitegroup should be 3.
Uri
_api/web/SiteGroups(3)/users
Body
{
"__metadata": { "type": "SP.User" },
"LoginName":"i:0#.f|membership|jane#contoso.onmicrosoft.com"
}