Here is what broad format support claims hide:

Video Editing Software File Format Compatibility Chart: What Yours Is Hiding
Image via Wikimedia Commons
  • MKV: Premiere Pro partial (codec dependent), DaVinci Resolve yes, Final Cut Pro no, CapCut mostly.
  • MOV/ProRes: Premiere Pro yes, DaVinci Resolve yes, Final Cut Pro native, CapCut limited.
  • WebM/VP9: Premiere Pro needs a plugin, DaVinci Resolve yes, Final Cut Pro no, CapCut no.
  • HEVC/H.265: Premiere Pro yes (with hardware), DaVinci Resolve yes, Final Cut Pro yes, CapCut yes.
  • AVI: Premiere Pro yes, DaVinci Resolve limited, Final Cut Pro no, CapCut no.

Premiere's MKV support fails silently on H.265. Final Cut Pro pretends MKV does not exist. CapCut chokes on ProRes masters. DaVinci Resolve is the most honest of the bunch, and even it struggles with exotic audio in MKV. Sources: FFmpeg, HandBrake The fix is always the same: standardize on ingest. Remux or transcode everything to MP4/H.264 or ProRes before it touches the timeline, and format surprises stop happening. Once the format war is won and the edit is locked, ReelCut turns the finished video into platform-ready Shorts at $9.99 one-time per video.