Every signature will be different as data to be signed in each input will be different, that is what matters.
Here's random example transaction I just found, it spends exact amounts from multiple inputs, sent to the same address. https://mempool.space/tx/466ddadf42d82027411b2984a6b1b0f1d9631fb05f6e61d97e7634bf34119f2e
Click on "Details" there and compare "Witness" field of each input.