Copy a SPO team site to a private channel site

[Michal_Z]

Hi, 

Except for tools like ShareGate, are there any native Microsoft tools to copy the SPO site content connected to the team in Teams to its private channel' SPO site (not only doc libs but also lists created on the main team site)?

If not, what tool except ShareGate can you recommend? Is it possible in PowerShell?

/Mike

[#2]

As an explanation, we cannot wait any longer for Shared Channels in Teams to be available which has been introduced in 2019. We need to move the content of the team available in the General channel to a private one to be able to invite externals to collaborate in other channels within the same team.
Maybe you have any tips on what else can we do to secure the content stored on the site of the team?