It’s not explicitly stated in the docs but you need to specify a predicate too, that’s why you’re having an error. If you do not care about the predicate you can use TRUEPREDICATE for that.
Additionally argument substitution does not work with sort/limit clauses.
In your case your query would be:
list.Filter($"TRUEPREDICATE LIMIT ({offset}));
We will take care of upating the docs to make those two points explicit and hope this solve your doubts.