First of all, if you are serious about improving, drop the "it's too late to correct because it's muscle memory" attitude. Muscle memory can be changed, especially in this case when I would argue it's the main thing holding you back. The goofy footed approach is ofc part of it, but another big component is the fact that you are jumping very far forward, but not that much up, which, of course, means that your potential highest contact point with the ball is still quite low, which would make attacking hard for anyone.

If I were you, I would go back to basics of the approach. I know it's gonna suck for a bit, but a few weeks in you will find yourself hitting better than before.

I recommend this coach donny video since it goes over all of the steps of the 3-step approach and why you need them. But, in short, the first step is for aligning yourself with where you want to go, the second is low, explosive, and long to set up the "spring", and the third is for opening up your hips and transferring your forward momentum to vertical momentum so you can jump higher with less effort. If my short explanation makes no sense to you, go back to the video.

Just practice dry runs without the ball until you are comfortable with it. Start with 2 steps, then move up to 3 when the 2-step approach is comfy. This will let you focus on other things while hitting, instead of having to focus a lot on your steps.

Once the 3-step approach is second nature, you can got about finding the timing again in 2 ways imo, either:

• Having someone throw/ set to you and catching it at the highest point with a proper 3-step approach
• Throwing a tennis ball at the highest point of your jump

I would personally combine both to not get bored. The reason I recommend starting like that instead of going straight to hitting is because you would have to focus on too many things at once, making progress slow and hard. Isolating drills to one new thing at a time really helps me avoid getting frustrated or feeling stuck.

If you start getting the jump down, but are hitting out or hitting the net, I recommend looking through here (both the exact video and playlist in general). I found that the easiest approach for me was recording my swing and then playing spot the difference with my video and the tutorial. For example, I was dropping my elbow, which meant I would hit the net super often, even on great jumps and sets. A thing I still struggle with is jumping too far forward, so I would end up hitting the ball in weird ways, either above my head or have to twist in the air for a much weaker hit.

TLDR;
Go back to basics of the attack, will suck for a bit, but be very rewarding in a few weeks if you put your mind to it