From my reading it seems that Resolve runs fine on Linux with the exception of some codecs not being available.
My biggest concern is with playing footage inside of Resovle (I think the codec issue might affect this as well). My Sony A7IV records footage at 4k h264 (10 bit 4:2:2), the free version in Windows doesn’t playback this footage at all. MacOS doesn’t have this issue at all.
I’m assuming I’ll need to transcode my footage with ffmpeg on Linux the same as I do on Windows. Is that correct?
I would try a transcode to DNxHR, it's much quicker to edit with anyways since it's optimized for that. h264/265 is ridiculously resource intensive to edit.
How much bigger are the file sizes? I've transcoded to ProRes previously and that was on average 6x bigger
Here’s the bitrate table: https://avidtech.my.salesforce-sites.com/pkb/articles/en_US/White_Paper/DNxHR-Codec-Bandwidth-Specifications
Keep in mind these are listed in MB/s, so multiply by 8 to get Mb/s if you’re used to that number. HQ/HQX in UHD 29.97 for example is about 6.2GB per minute, or 375GB per hour.
How much bigger depends on your source footage, if you’re recording in say UHD 29.97 10 bit 4:2:2 at 400Mbps, then the DNxHR HQX version would be about double the size.
You can just remove the DNxHR proxies when done so the space isn’t being taken up.