She created account, But can`t pair cameras.
She shouldn't be pairing cameras (adding devices). Cameras are only in one account, so she can't add them to hers.
The normal process is for her to click on the link in the arlo email she was sent when you invited her, and then log into her account.
but can’t add devices…
Again, that part cannot be done (and shouldn't be needed).
Is the invitation still shown as pending in the main account? If so, then the problem is that the invitation hasn't been accepted.
When you set up friend access, did you select the cameras you wanted to share?
Invitation is “pending”. She/we follows the link in the invitation, and creates a account for her. We log in with the app. But there is no cameras. And I have checked alle cameras for sharing 🤔
Are you using a mobile device to do this? If so, try using the web client from a PC. Click the invitation link and then sign in to the Arlo account you're sharing the cameras with. Do you still experience the same behavior?