I noticed that a lot of models for fan grills mimic metal ones - not ideal for strength since the properties of the materials are so different.
I couldn't find a 3D printable fan grill that I liked, so I made a few of my own. This one has Hexagons.
It is modeled at 2mm thickness. You can scale the Z-height in your slicer to make it thicker if needed. I haven't tested it for noise, please comment if you have that ability.
The author marked this model as their own original creation.