There are two baggage allowance systems, the piece concept and the weight concept.
The piece concept measures how many pieces of baggage you have. In your case on Emirates, the rule is that you have two pieces. Each piece is considered separately and may weigh up to 23 kg. You do not have a 46 kg allowance. You have two pieces.
The weight concept gives a total weight and is unconcerned about how many pieces you bring up to the total. [A practical limit may apply, usually ten bags.]
Emirates uses the piece concept on its flights to/from North America. (See https://www.emirates.com/english/help/faq/490107/weight-and-piece-concept.) You will not be permitted to pool your allowance, because that would change your allowance.
In practice you may find that the airline check in agent will overlook a small breach of the rules. But you may find they do not, in which case you will either need to repack your bags or pay the appropriate overweight fee.
If you have booked this as one ticket, then Emirates' allowance applies on all legs under a US regulation (it will be encoded on the ticket as two pieces). If you have booked it as separate tickets, then each carrier's policies apply leg-by-leg.