It's typical to provide for as much as 0.2 mm difference between joining parts, to ensure that once printed, there will be sufficient clearance for assembly. For a tighter fit, change the clearance to 0.15, although going as far as 0.10 is risky. If you are using an online printing service, they may specify the acceptable clearance in the fine print.

SketchUp is known for creating non-3D-printable models. Consider to upload the STL file to an STL file checker to see if you were able to avoid the usual pitfalls.

How much flexibility do you require? PETG has a decent amount, and nylon is astonishingly strong and flexible.