Welcome to WaveLab. iZotope has made some strange decisions lately including removing the standalone Ozone app but as handy as that was, it was never a great place to master an EP or album since you couldn’t really sequence an album or group of songs in the correct order, set the song spacing, add track markers, metadata, etc. and render all your master formats.
Anyway, WaveLab is a great place to do all this.
You could open each song as its own file in the Audio Editor, and all those files can all be in the same File Group. In fact, never use File Groups and have the File Groups bar hidden to provide a little more screen real estate. I don’t use the Audio Editor method for any real work though. I prefer the Audio Montage, even for mastering singles. The Audio Editor is much more of a destructive environment compared to the Audio Montage which is more like a typical DAW session where basic things like fades can be fine tuned and undone.
The thing to know about WaveLab if you’ve never used it is that if you do work on files directly in the Audio Editor, you can only insert plugins in the (global) Master Section which is not automatically saved and loaded when you close and open each file. There are some settings to help but it’s not as automatic as you might expect. In other words, if you load a plugin chain in the Master Section and dial in the plugin settings, if you play another file, it will get the same settings unless special care is taken. That’s why I call it the Global Master Section, and also why I never use the Master Section for any plugin processing. My brain doesn’t get along with it.
I highly suggest working in the Audio Montage portion of WaveLab. This would allow you to load in all your songs, put them in a certain order, adjust spacing between songs, add track markers to offset the start of each song/track with the first downbeat so there is a short breath (if desired) before each song starts and so the proper song spacing is maintained when you render your master WAVs.
Aside from all that, you can then insert plugins as needed directly on each song using Clip Effects in the Inspector of the Audio Montage, as well as anything you’d like applied globally after the Clip Effects by inserted a plugin or plugins in the Montage Output section.
All of that is safely stored in the .mon file for the Audio Montage as you would expect any normal DAW session to operate.
Using the Audio Editor and Master Section could be considered more direct but it’s also more limiting and confusing in my opinion, plus there is room for user error if you forget to load and save the correct Master Section plugin chain for each song as you go between songs.
In the Audio Montage, you can even use the great Meta Normalizer option to get all the songs in the Audio Montage to the same mathematical/scientific loudness and then fine tune by ear from there, but with the right settings, the Meta Normalizer can get a group of songs very close to the same perceived loudness. I suggest the “Top Of Loudness Range” option in the Meta Normalizer because that sets the loudest part of each song to the same loudness which to my ear is more musically accurate than Integrated LUFS.
Here is a screen shot of an album I mastered. I already dialed in 95% of the sound using my analog gear and then in this particular audio montage, I did a few per song adjustments using Clip Effects in the Audio Montage, simple level automation, all followed by a final limiter (and eventual dither) in the Montage Output Effects section.