Here's a vid DIY to replace Engine air filter
I read on this forum that the GLC300 4matic has the same engine as C300 W205. And yes, you will see that the engine bay looks just like ours.
I installed a Mann C28004 purchased, along with Mann cabin filter, CU25002, from Rockauto.
I did it at 20,000 miles and it was moderately dirty. As in the video I vacuumed out of the box some debris and pieces of leaves.


