Are you going to hire them as your employee or as third party experts?
If you are going to hire them as employees and if they will work form outside India then no TDS and GST needs to be paid.
If you hire them as third party service provider then you might have to deduct TDS depending of different nature of services and we need to check agreement of each kind of services.
Further, GST also might be required to be paid under reverse charge if you wish to hire them as third party experts as it will be import of service.
So as you are saying if are legally comply with all requirement to establish an employer employee relationship then you might not be required to deduct any TDS or pay any GST.
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