The relation method actables (ActsAs::ReflectionsWithActsAs) is not documented in the README (I was about to propose a feature request for this functionality 😅, I've added a small PR to add it in there).

That aside, actables seems to only work when the default name of actable is used (it uses hardcoded where(actable_id: ...)).

So a configuration like

class Product < ActiveRecord::Base
  actable as: :producible
end

class Pen < ActiveRecord::Base
  acts_as :product, as: :producible
end

Product.where(price: 0.8).actables

will not work.

I believe to make actables work with differently named relations, the ActsAs::Relations::ClassMethods needs to define a way to retrieve the as parameter, or pass it along somehow. It would also need to define a method on the class instance with the plural of what is passed to the as. Something along the lines of:

...

singleton_class.module_eval do
  include ActsAs::ClassMethods
  
  def <as.to_s.pluralize.to_sym>
    acting_as_model.where("#{as}_id" => select(:id))
  end
end

I'm afraid I do not quite know how to do that, or I would suggest a pull request myself. However, perhaps it is possible for you to add this?