The main difference between the Linguica and Chorizo in in the spices that are used to make the sausages.
The Linguica and Chorizo are similar sausages but they are made using different spices.
The Chorizo sausage is made of and is redolent of paprika and garlic, and is dry cured, so it just needs to be sliced before eating.
The Linguica is basically just a Portuguese sausage that is similar in structure to the Italian luganega sausage and it's a coiled pickled sausage that is spiced with paprika and garlic, that needs to be cooked before serving.
The Chorizo sausage is ready to eat without cooking it first while the Linguica sausage needs to be cooked and is just made different.
The origin of both the Linguica and Chorizo are different as well.