Unlimited 3D Flags by Make_Believe on CGguy
https://elements.envato.com/unlimited-3d-flags-23N38L4
Free 
221 Looping World Flags by Pixamins on CGguy
https://elements.envato.com/221-looping-world-flags-V2M53LV
Free 
World Soccer Cup – International Soccer Package by MotionRevolver on CGguy
https://elements.envato.com/world-soccer-cup-international-soccer-package-BGS6EZR
Free