Hello @janka.boettiger​,
Welcome to the LastPass Community!
I hope this message finds you well. Yes, you can create a folder and not add any item inside it. The process is the following: Access your Vault > All items > Hover over the red bubble with the + sign > it will come up at the top a white bubble that says add folder > click the bubble and you can give it a name to the folder. You can find more here: Manage folders in your LastPass vault
Kind Regards,
Alejandra
LastPass Support