Trust by a Pvt Co.

I think not it's not a right way

A trust which has not been registered cannot be treated as a person, hence shares  cannot transfer to an unregistered trust. However, it could be registered in the names of one or more trustees. However, shares can be registered in the name of a trust or co-operative society, if it is registered. Hence, a pvt ltd. company can  transfer its shares to a registered trust. 

This is not correct way.

For Listed company ,SEBI(SBEB) talks about trust route to held shares for benefit of employees where trust acquires shares from secondary market for options granted, I don't think that private company has to create any trust and then transfer it to employee when he/she exercise option because of no secondary market purchase, you can directly adopt ESOP scheme ( whether RSU/SAR etc) and grant option with vesting schedule, or Phantom Stock is far better. because in private company no open market is available to sell shares so phantom stocks are better