Hey Egil,

If I’m understanding correctly - you are launching a few different collections and want users to subscribe specifically for each?

You have a few options but I recommend you send all of your subscribers into your Main List and in the button settings of your pop-up/embed form you can update the profile property to match the specific collection launch for each form.
 

So Collection Name Alert - YES or Source - Collection Name Alert for example

 

And then you can create Segments that filter for these values you set so that you have different groups to target for launch emails!

Hope that helps!