So uhh... I might have actually found a solution to this problem while trying to mod the fist fight input behaviours.

In the script r4player.ws, under "event OnCombatStart()", there's literally a line that says:

theGame.CreateNoSaveLock( 'combat', noSaveLock )

If you literally just comment out that line, it seems like it lets you save at any point during a fight. I remembered your post so I tested it out. So far I can save freely during fist fights and mob encounters, and it loads up into the same state (health and positioning), with Geralt in a neutral stance. Obviously there could be some unintended consequences to using this? But I actually think CDPR just put it in to stop players from cheese saving. I've found other comments littered around the scripts, describing how they buffer the 'parry' command and check how much you're using it specifically so you can't spam it to cheese a riposte. I mean I imagine it might interrupt some events so you maybe don't want to use it during major boss animations or whatever, but for the start of combat and at any regular time it'll probably work fine?

Anyways if you wanna try it out, it's easy. Doesn't take any real knowledge and it can be done in less than a minute:

• Navigate to the Witcher 3 install folder (Steam/GOG/PC/whatever)
• Navigate to The Witcher 3 Wild Hunt\content\content0\scripts\game\player
• Copy 'r4Player.ws'
• Navigate to The Witcher 3 Wild Hunt\mods
• Create the following New Folder tree in mods: modSave\content\scripts\game\player
• Paste 'r4Player.ws' in the new mods...\player folder.
• Open this pasted 'r4Player.ws' with notepad
• Edit: Find: Copy& Paste: theGame.CreateNoSaveLock( 'combat', noSaveLock )
• When you find that, add // in front of it to comment it out. Or just delete it, same result.
• Save and exit the file

Next time you load up the game you'll get this RedKIT splash screen that'll compile in the mod. Should let you save wherever after that.