Swap between phones with esim

Hello, I signed 3 years contract and got a new samsung phone with tmobile. Recently I want to switch back to old phone-iphone cause samsung is kind of difficult with so many gadgets. Is it possible to transfer esim to my old iphone? I still paying the samsung phone according to the contract. The phone will be at home to play music or take photos- not giving to someone else to use- and maybe ill switch back to it after few months again. I used to swap between new and old phones back in the day with sim card. I dont know if i could do the same with no fees cause esim always require imei of the phone