Register media conversion in model that extends

[MarcelWeidum]

Base Post model (with media)

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;
use Spatie\MediaLibrary\MediaCollections\Models\Media;
use Spatie\MediaLibrary\HasMedia;
use Spatie\MediaLibrary\InteractsWithMedia;

class Post extends Model implements HasMedia
{
    protected $fillable = ['title', 'description'];
    protected $table = 'posts';

    use InteractsWithMedia;
}

The PostCopymodel that extends Post and where I want to register the conversion

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;
use Spatie\MediaLibrary\MediaCollections\Models\Media;
use Spatie\MediaLibrary\HasMedia;
use Spatie\MediaLibrary\InteractsWithMedia;

class PostCopy extends \App\Post implements HasMedia
{
    public function registerMediaConversions(Media $media = null): void
    {
        $this->addMediaConversion('thumb')
              ->width(600)
              ->height(600)
              ->nonQueued();
    }
}

If I get the media from PostCopy of course I get no media because the media is on the Post model.
I don't want to copy all the media to the PostCopy model.

Has anyone got a solution for this?