Buying alt coins using USDC

What is the best option for buying altcoins with USDC/USDT?
I have some USDT on the Polygon network and want to buy a few different tokens, considering all of them have pairs or routes in Uniswap, what would be the more economical of the two options , slippage vs Coinbase fees.

Option 1) Send my tokens over to Coinbase and then trade there?