Imagine that you are in front of an Electronic Engineer so what will you ask him/her to invent?
which invention is missing in your opinion?
we have wireless data transfer and wireless power transfer...(they are in communication field,not electronic,so i will answer u with doubt)
wireless data transmission is already done (for example WIFI).
but wireless power transmission still has some problems for example their efficiency.so long range wireless power transfer will lose a lot Energy.