Reduce the resolution in Fusion on the fly by using Proxy Mode. Select the quality of the proxy via the Timeline Proxy mode of DaVinci Resolve and activate the proxy via right-click on the Fusion transport bar.
Free 5h Fusion course:
https://vfxstudy.com/product/rfb/
Training for DaVinci Resolve & Fusion:
https://vfxstudy.com
Fusion Keyboard Shortcuts:
https://vfxstudy.com/tutorials/keyboa...