Create Custom Schema that is just table names?

The problem I’m having

I have a pre-set database schema in teradata that cannot be changed, but I have write access to said schema. However, I’d like to group all my said objects together under a custom “prefix” for the table names without manually maintaining this in file names. Is there a way to do this using custom schema’s or any other aliasing features that can be broad to a set of models and not individually set in each SQL file?

I tried placing a custom schema in my project.yml, but i’m just getting access errors that my account doens’t have “create database” access. So I assume that isn’t working as I expected.