In Germany there are stickers that prove that my vehicle has access to the LEZ. Does the Antwerp LEZ have similar stickers?

No! Antwerp does not have these stickers.

Please note: some commercial companies (e.g. Green Zone) will offer to complete the procedures for ensuring your vehicle is authorised to enter the Antwerp Low Emission Zone against payment, and they provide a sticker for their customers. The City of Antwerp is in no way related to this service. On the website of the City of Antwerp, you can register your vehicle or purchase an admission yourself, without extra administrative costs.

You will not be required to show any physical document as proof of access to the Low Emission Zone in Antwerp. The check is performed using the Vehicle Registration Plate and is fully automated. Companies that sell so-called environmental stickers as proof do so entirely at their own initiative. These stickers have no legal value.

The website http://urbanaccessregulations.eu/ contains all the necessary information about low-emission zones in Europe.