Unfortunatly...Those beams need to stay where they are. You have a hip roof and there is only one way to support a beam, it needs to rest on a bearing point, which in your case is the wall it is on.
Yes an engineer would be the best way to know exactly what you need to tell a contractor. At this point it will tend to be on the overbuilt side when you are finished. Any engineer with that span will go for Laminated veneered lumber( LVL) or a sandwiched steel plate between the wood.
I can see deflection already in that beam, but it could be due to the crack.
It will cost around $500 for an engineer to do the calculations, that would be my suggestion if you want to keep the wide open space.
If you want to go the less expensive route, put in a post and make sure it transfers the weight to the foundation or a footing under the home.
Thanks for the pictures, they helped alot.