Swiss stamp duty accounting

I am in need of a freelancer who can assist me with Swiss stamp duties calculations and accounting for securities transactions performed by Financial Intermediary's clients booked in non-Swiss custodies. We are a Swiss asset manager, and some of our clients have their accounts with non-Swiss banks and brokers (like Interactive Brokers, for example), and we need to understand if we need to calculate, charge and pay Swiss Stamp duties on any of our clients operations. I require ongoing support as this is the ongoing business. I am not sure if our accountants will need help with filing and submitting the necessary paperwork, so I would appreciate some advice on this matter.

Ideal skills and experience:
- Knowledge of Swiss stamp duty regulations and compliance for securities transactions
- Experience in providing ongoing support for stamp duty for operations of Swiss financial intermediary's clients booked in non-Swiss custodies
- Expertise in filing and submitting necessary paperwork for stamp duty compliance
- Strong communication skills to provide advice and guidance on stamp duty compliance.