Generally, unless you are a Personal Trainer employed by the gym you're running sessions in, you will not be able to use a Hussle Pass to access the gym facilities in order to train clients. By purchasing a Hussle Pass, you are accepting both the Terms and Conditions of Hussle, and the gyms which you visit - most gym Terms and Conditions will prevent you from running Personal Training sessions.
If you do decide to train a client, you may be asked by gym staff to stop, or to leave the premises.
However, you can always check with the gym to see where they stand on Personal Training - if you have clear confirmation from the gym that you can train a client within their facilities then go ahead!