Hello ! I'm Aymeric, and I'm here to help !
Open Microsoft Edge and click on the three dots at the top-right corner of your screen. Click on Settings, and on the new tab that opens, click on "Languages" , on the left.
Once done, can you provide a screenshot of what's displayed on the screen ?
You'll have to make sure that the "Offer to translate pages that aren't in a language I read" option is enabled. If that's not the case, the icon will not be shown.
Looking forward to your answer !