Color artifacts and smoothness on macOS with GoPro videos

[Sintek]

Hello there, as in the subject I incur in some problems during playback on VLC.

My hardware:
- MBP 16" 2019 i9 32gb RAM w/ AMD Radeon Pro 5500M 8gb integrated graphic card, Catalina 10.15.7;
- GoPro Hero 11

"My software":
- DaVinci Resolve 18.1

I'm a total newbie to video editing and encoding 'cause I'm from music world so, be patient, please.

I use my GoPro to make H.265 videos, 4k or 5k at 50/100/200 fps, depending on how much idiot I wanna be....

Importing on my mac and playback in VLC, clips are amazingly smooth, fluids and frame-full.

1st PROBLEM: COLOR GRADED CLIPS

BTW, clips seems to have color grading artifacts that: importing them in DaVinci Resolve make the difference with the original clear, like some algorithms are applied.
Searching all over the web I didn't find anything that seems to help: any definitive solution?

2nd PROBLEM: STUTTERING WHEN PLAYBACK AFTER EDITING

I made simple trims and cut edits in DaVinci Resolve, to remove and paste parts of clips.
Once exported (in MP4 with H.264 codec because I want to playback videos on my shi**y TV with USB 2.0 ports and without H.265 support), lags and jumps appear: little but noticeable.
This problem only appears in VLC: when I played back my edited videos in QuickTime or my TV they seems just like the original (obviously with little less quality because of 5K to 4k downscale required by Resolve free Version and less bitrate deliver).

Any missing preference setup here too?

Here's my DaVinci Resolve deliver settings:

https://ibb.co/6YCh77q

https://ibb.co/tx3nXWs

BONUS QUESTION: does a USB 3.1 flash drive "hit hard" USB 2.0 tv port if I try to reproduce edited videos with more bitrate (ex. 200.000kbps)? I mean, can I damage the port if the data flux generate more current than USB 2.0 ports (0,5A) can handle? Or lags video occured?

Thanks and forgive my bad knowledge......

[Sintek]

Anyone? Less talk.
1) in VLC, original GoPro clip play smoothly, the 4k h.264 edited version lag and stutter. This happens only in VLC, QuickTime plays it smoothly. Why? ;
2) in VLC, colors and gamma are "adjusted", both the original clip and the edited one, even if I export in Rec.709. QuickTime plays the edited Rec.709 correctly, with no color changes. Why?

Thanks in advance and have a nice day!