So I have two models: Article and Tag, and a m2m relationship which is properly set.

I have a route of the kind 'articles/tag/' and I would like to display only those articles related to that tag

I have sorted out this problem already but I am looking for a more elegant solution including pagination but I am not able to use paginateover the articles list because it's not a queryset

I need a queryset of all articles linked to a certain tag. I have tried order_by in many different ways and failed miserably.. I wasnt able to find something useful in the docs, any ideas?

While OP's problem was lazy="dynamic", I ran into this issue with a relationship which was already using that. In my case, the problem turned out to be that I was using relationship() imported directly from sqlalchemy.orm. Instead, I needed to use db.relationship() to get the version of the method wrapped by Flask-SQLAlchemy.