You may want to verify this with Refinitiv Helpdesk by asking if there's a way to do this using =TR function in Eikon Excel.
If there's a way to do this using a formula in Excel, then this formula can be replicated using Eikon Data APIs.
The Refinitiv Content Helpdesk can be reached using Contact Us capability in your Eikon application.
Or by calling the Helpdesk number in your country.
Or at https://my.refinitiv.com/