Action VFX Transitions | After Effects by VFXgenerator on CGguy
https://elements.envato.com/action-vfx-transitions-after-effects-6A3F5D5
Free 
Fire And Smoke Transitions by 2DFXAnimation on CGguy
https://elements.envato.com/fire-and-smoke-transitions-HYGZPVS
Free 
VFX Transitions | After Effects by VFXgenerator on CGguy
https://elements.envato.com/vfx-transitions-after-effects-AHFJDHJ
Free