Get rendered values from Grid

Hello,

i am trying to realize a generic grid data export to a reporting framework. I use:

final List<Order> collect = this.grid.getDataProvider().fetch(new Query<>()).collect(Collectors.toList());

to get all the data from the grid. But the dataprovider provides only raw data and i need the already formated / rendered data from the grid.
My idea was to reuse the available rederers from the gridcolumns in combination with the raw data. To get the renderers i used the following line of code:

this.grid.getColumnByKey("freight").getRenderer();

Now my Question: How to reuse the renderers from the grid to get nice formated values to export. Or is there another way to get the allready formated values?

Regards Christian