Since I didn't find all the information online on how to start a new game and import a new character from the character creator I'll post here the method I had discovered.
In program files (x86)/steam/userdata/174234212/2054970/remote/win64_save
Delete all files.
Then start the character creator and make a new character, it doesn't matter how because you won't use it, finalise it and say that you want to import this new character to the DD2 game, then select the character you actually want to use, say that you want to make changes to it then finalize it, again the message that asks you if you want to import this character should show up, say yes.
Go to the same folder as before and again delete everything except SS1_data000 and SS1_data00-1.
On steam, in game properties disable steam cloud.
Launch DD2 and this time you should be able to start a new game and import the character at the same time.