This definitely looks like something wasn’t installed correctly. Did you copy the files in “Important - Read This”/Game Files to the same location as your strive.exe prior to activating the mod in your mod menu?
Viewing post in Aric's Expansion Rebred
Did you do the final recommended step of either deleting/renaming your Strive/Backups folder or copying/overriding the files in it? If not, it likely replaced your modded files (that you overrided the vanilla files with) with the vanilla files in backup.
I'd recommend deselecting the mod in the mod panel, closing the game, renaming your backups folder to something like "backup-backups", copying the files inside of "Put in Strive Game Files" to your exe (note that you need the files INSIDE of that in that folder there, not the "Put in Strive Game Files" folder itself. If it makes you override files you're doing it right), then restarting and activating the mod.
I just checked the AricsExpansion v0.9.2 zip and the Put in AppData.Roaming.Strive is definitely inside of"Important - Read this before installing" . If it isn't showing in your zip, your download might have been interrupted. I'd recommend redownloading the mod if that's the case.