Conditional access for Microsoft 365 admin centers

[starbuck3k]

A client would like to enforce sign-in frequency and trusted location for access to any of its Microsoft 365 admin centers (e.g., SharePoint AC, Teams AC, Exchange AC, Security AC, Compliance AC, etc.).

Is there any way to enforce these restrictions through conditional access policies and without specifying "All cloud apps"?

[#2]

Trusted locations can only be enforced via CA, and you'd probably want to use the "Office 365" app as a target therein.
Outside of CA, you can enforce an idle timeout for any web-based app via https://learn.microsoft.com/en-us/microsoft-365/admin/manage/idle-session-timeout-web-apps?view=o365...