Lyckades få det att fungera så här, ser inte perfekt ut men det gör jobbet:
let productLists = await ProductList.findAll({
where: {
slug: ['recommended', 'new_and_promos']
},
include: [{
model: Product,
as: 'products',
include: ['attributes', 'images'],
where: Sequelize.literal('`products->ProductListProduct`.`position` < 8')
}],
order: [
[
'products', ProductListProduct, 'position', 'ASC'
]
]
})