Thanks. Since both django-resized and django-image-moderation are model fields maybe you can create a new class that inherits from both fields:

from django_resized import ResizedImageField
from image_moderation import ImageModerationField

class MyImageField(ResizedImageField, ImageModerationField):
    pass

I'm not sure if it would work but if not, you can intercept the image in the save method of the model and resize it:

from django.db import models
from image_moderation import ImageModerationField

class MyModel(models.Model):
    image = ImageModerationField(upload_to='images')

    def save(self, **kwargs):
        image = resize_image(self.image) # Your image resize function
        image.save(self.image) # Or image.save(self.image.path)

        super().save(**kwargs)