Sometimes (for unknown reason) FodyWeavers.xml
cannot be added automatically when the package is added. You'll need to add it to the root of the project manually:
<?xml version="1.0" encoding="utf-8"?>
<Weavers xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="FodyWeavers.xsd">
<Costura />
</Weavers>
I'm using Fody 4.2.1
and Costura.Fody 3.3.3
I hope it helps 😊