🇦 The perceived difficulty of the adventure be roughly the same, but the encounters might be slightly different in monster count or type.
🇧 The number of creatures in encounters be roughly the same, but the encounter difficulty might slightly harder or easier then the OG adventure would have been.

Also, lean in to the trauma of the injury.

But any practical advice would depend on the prevalence and effectiveness of magical healing in your game world.
Does magic just speed up healing or does it restore flesh? Does it make the pain go away or just numb it? Is the restoration perfect or can there be flaws and on what scale?

There isn't really an existing system for this, and adding something can be fraught with pitfalls. What you would be doing is essentially lowering a player's effective level and this can skew combat encounter planning.

Adding something like this should be discussed in session 0.

I will say one other note: if your players are power gamers PL -3 monsters are very weak and should probably have double their number or made Elite. The final encounter was a PL +2 and 2x PL -3. (3 PCs total) The boss did all the heavy lifting and the others were basically just two mobile hp bags.

I don't know how much streaming you do. But the one thing I look for in streams or podcasts of any kind is the audio quality. Bad volume levels and poor audio clarity will turn off listeners really fast. So please do lots of sound checks ahead of time.

That depends, does it involve shenanigan's and such?

One thing I learned is that running a social group like this takes a lot of time and money, so I am setting up avenues for people to contribute to it. Buy Me a Coffee seems like a straightforward way to do it (and they even have a mobile app!).

Didn't WotC buy roll20? I don't think they are going to make any effort for a competitor's game.

If you are doing this for political reasons, I am so sorry. It makes me so mad seeing what is happening around the country.
If you are doing this for unrelated personal reasons, CONGRATS. Be you!

I love having the physical books. But I've found reading on a tablet is a decent second place.

I don't use music in my games. I have audio-sensory issues and I play with some players that also have audio problems.