Potential Paths: Path 1: Using Quizizz to transform the quiz into a gamified and interactive format, leveraging its vast library of teacher-created activities. The Quizizz AI Enhance feature could be used to customize activities, including simplifying and translating questions. For auto-grading, users might have to rely on Gradescope, which offers AI-assisted grading. Path 2: With Quizalize, the teacher can transform the existing quiz into a fun class activity and offer students immediate feedback on their performance. However, to use AI grading, users would still need to integrate with Gradescope. Unlike Quizizz, Quizalize does not provide an AI-enhancement feature.

Final Narrative: To convert your existing quiz into a Google Form with interactive features and auto-grading functionality, I recommend utilizing both Quizizz and Gradescope.

Start with Quizizz to transform your quiz into a more engaging, gamified format. With Quizizz, you'll be able to make use of its extensive library of teacher-created activities to add interactivity to your quizzes. Additionally, you can use the Quizizz AI Enhance feature to customize your quizzes as required—this can range from correcting spelling errors or simplifying questions, to translating them into different languages.

When it comes to auto-grading, Gradescope is the ideal tool. Its AI-assisted grading feature will help you efficiently grade your students' responses. Plus, Gradescope enables a dynamic point adjustment rubric, which allows you to adjust grading criteria even during the grading process.

Together, these EdTech tools should provide a comprehensive solution that suits your requirements. Just remember, you need to create your quizzes in Quizizz first, then use Gradescope to autofill the responses for grading efficiency.