First some background information.

I have an old website (not wordpress) => https://www.carnaval-radio.nl from now on, I will call this old.

I have a new website (in wordpress) => https://carnaval.bynick.nl from now on, I will call this new.

I have imported all posts of the old website through an RSS feed into my new website. The links to all the images inside those posts remain linking to the old website.

• The images on the old website are served trough an axd file
  https://carnavalsradio.nl/image.axd?picture=2020%2F2%2F86386253_2945403745507075_1513521371026554880_n.jpg
  (So I can’t just change the path everywhere)

Is there some kind of plugin that let’s me download all the images, replace all the links in all posts, and serve those images trough my new website? Or are there perhaps other ways to do this?