According to the oracle documentation, we can hide the apply button in the data model in OBIEE 126.96.36.199.. version. However, I have checked on 188.8.131.52.0,184.108.40.206.4 version there is no features in data model to hide the apply button as show in the figure below. Is it available in latest 220.127.116.11.0 version only?
I believe that the "Apply" button is in reference to the Parameters. You do have the ablility to either show the Apply button or not. You can set this on the Parameters page under Display options -> Show Apply Button.
I am working with Oracle Business Intelligence 18.104.22.168.7 version and I am able to set this property.