Bitcoin core internal transfer problem
Things you are trying to accomplish is you are try to transfer your bitcoin currency from one wallet to another wallet through internal bitcoind core system. whilst, you do not want to deduct balance. there is no api there which can prevent balance deduction. 

bitcoind core has build their api if you tweak their code to prevent deduction of money. you can say you hacked bitcoin and your name will be breaking news! in theory you talk awesome, but practical way impossible. 

Bitcoin virtual money is invented by satoshi nakamoto. also he can not do this things. if any person do transfer like you said. bitcoin will have zero value. 
reason: people will start installing core/generate new bitcoin daily/earn money/no mining forever. just earn money. practically your idea is worthless, impossible.