We stayed at the Marriott downtown on Cass St. They shuttled us for free to the port. Nice, clean rooms.
I stay at the Marriott downtown every year for our company Christmas party and there are folks there that take the shuttle all the time and it is free.
Downtown has courtyard residence inn both have shuttle services and it's near the riverwalk
There are several Google and choose based on your preference.
Best to Google and compare
Thanks! Your answer is awaiting moderation.