SharePoint Online: Move Subsite to Another Site using PowerShell

Requirement: Move Subsite to a new site in SharePoint Online.

How to Move a subsite in SharePoint Online?
Let's move a subsite to the root site in SharePoint Online using content and structure page:

• Go to Site settings page >> Click on "Content and Structure" link (https://tenant.sharepoint.com/sites/your-site-collection/_layouts/15/sitemanager.aspx)
• Select the subsite from the Treeview >> Click on "Move" from the subsite's context menu.
  
• Select the target site and click on "OK" to move the subsite to the new site.
  

This moves the subsite to another site in the same site collection. We can use this method to move SharePoint online subsite to another subsite too.

PowerShell to move subsite to another site in SharePoint Online :
Let's move subsite to root site with PowerShell.

#Set Parameter values 
$SiteURL  = "https://crescent.sharepoint.com/sites/marketing/us/2017"
$NewSiteURL = "/sites/marketing/2017"

#Connect to PnP Online
Connect-PnPOnline -Url $SiteURL -Credentials (Get-Credential) #-UseWebLogin

#Get the Web
$Web = Get-PnPWeb

#Move the site to New URL by Setting relative URL
$Web.ServerRelativeUrl = $NewSiteURL
$Web.Update()
Invoke-PnPQuery

This moves the subsite under https://crescent.sharepoint.com/sites/marketing/us/2017 to https://crescent.sharepoint.com/sites/marketing/2017. Please note, this method works only within the site collection!