itch.io

What you're describing is exactly what takes art teams so long in games. If you want it to look bespoke and custom, you're going to have to do a lot of things by hand. Automating things pretty much always going to look way worse (especially in pixel art, given how punishing the style is).

Usually with pixel animations, you can put the placeholders in a separate folder and your actual character in another. then you go layer by layer, putting the limbs in the right spots which is usually just copying and pasting across the frames and moving them. Then you do have to do some hand painting on each frame to make it look good but personally i've found that the actual movements (like this pack) takes most of the time. 

Another way to do it is to model your character and animate them in 3D. Then export them at your pixel resolution and make it into a spritesheet. This works quite well, especially if you're working with 8 directions. You're going to have to look into how to export images so they're pixel perfect, but Blender does it quite easily. You can even make animated normal maps that correspond to your character to do dynamic lighting.

Good luck on your quest! I hope this helps a little, but feel free to completely ignore this :)