Interpreting rooms with Relais modality

[FELCOS]

Hi everyone. please help me if you know the solution.

1) What type of Zoom contract is needed to be able to hold a meeting with "relais" interpreting?

The relais interpreting is when the interpreter translates both from the speaker and from another interpreter's translation. Therefore, the interpreter must be able to hear both the speaker's audio and that of another interpreter through headphones.

For example:

Interpreter 1: Spanish-Chinese.

Interpreter 2: Italian-Spanish.

Speaker: Italian.

Development: Interpreter 2: translates the Italian Speaker into Spanish; Interpreter 1 (who speaks Spanish and Chinese but does not speak Italian) listens the Spanish text from the interpreter 2 (who translates from Italian to Spanish) and translates into Chinese. This speaker 1 needs to have access to the voice of the Interpreter 2, but, also, access to the voice of Speakers when it is from Spanish or Chinese. 

Summary: 3 languages, 2 interpreters, with relay modality.

2) Is this function possible with the Zoom PRO contract?
3) And, how is this function managed? How many rooms are needed, for 2 interpreters and 3 languages? Are there clear instructions to manage this function? 

Thank you to everyone who can support me.