Reg : 4 to 10 Hours YT Video - Big File Size 4K (64 to 80 GB) - MKV to MP4 converter (Please Help)

Dear Friends,

Hope you all keeping well ?

Friends, I am working on YT project and my videos is from 4 hours to 10 hours (FCPX - Mac Pro 2020) but really struggling due to big file sizes.
My Video is in 4K and file size is 64 to 80 GB after using handbrake and MKVtool .. File is in MKV and I have tried VLC to convert into MP4 but taking ages to convert.
I have tried handbrake making MKV to MP4 again but due to big file its taking so so long.

Please help me to get best option possible to resolve from MKV to MP4 quicker or Any other solution to make all this process fast ?

Please share your expertise.

Thanks

You are rendering your files in a wrong codec.
You should use H.264 mp4 and play with bitrates to find good quality and small file sizes.

Later you can re-encode videos in other compressed formats, but it requires powerful hardware to do it fast.