RR Nougat/Oreo has a built-in system app remover, but I don't think it has made to Pie. If you want a native solution just reboot to recovery (or use any file manager with root access) and delete the folders from /system/app and /system/priv-app.Is there a system app remover built in to the ROM? I tried Titanium Backup like I usually do, but it's not getting the job done (maybe a 9.0 Pie thing?) I'd like to remove things like Browser, Email, Messaging, Trebuchet, etc.
There are other ways to remove system apps but keep in mind that they'll come back every time you update the ROM. It may be a good idea to simply disable these apps instead, I did that myself with Android Setup.
Just used Link2SD to remove Trebuchet and can confirm it works. But as I mentioned here removing Trebuchet will also break the new recents, reverting to the pre-Oreo style.