In my opinion the problems that arise with free will is that Frida would always be the one to go back in time to become the Frida Kahlo, which mean free will does not exist in this case. Free will does not exist because every action have a reaction and actions arise as consequence of the initialing action. Because she was named after Frida Kahlo and the invention of the time machine, it caused/led her to choose the path to go back in time and become the famous artist. Which means she would not be morally responsible for the absence of Frida Kahlo if she did not choose to go back in time.
Yes, Frida created a paradox by going back in time. The grandfather paradox was used in this scenario. Because she went back to time