Hello Alvaro! If it is the actual model of Eve Aqua it should automatically use Thread to communicate with the HomePod mini. Nothing to set here.
Please check: In the app Eve
Settings > Thread Network
After opening, wait 1-2 minutes with the screenshot until Eve has analysed the Thread network.
In case the result is not as expected, please open a ticket in our support system: https://www.evehome.com/en/support/ticket
Best regards, Volker
May 16, 2022