This members-only tutorial provides the steps to define a custom function that returns the value of a custom field set using Advanced Custom Fields for a taxonomy term so it can be used in PHP Function Return value for showing taxonomy term-specific values in Oxygen.
Note: The following steps assumes that you have already created the field group, attached it to your desired taxonomy, populated the fields by editing the term pages in the WP admin, and created a Oxygen Template that applies to all or some of your terms.