I found this problem interesting as well as a useful addition, so I took the time to create the curve presets, so they can be pasted in the editor-2.json file found in the settings folder of the user files directory.
NOTE: The last two rows at your link cannot be reproduced in Spine, but all the other ones yes, following the logic described here by which the four numbers you find on that website linked in the first post correspond to x1, y1, x2, y2 which can also be found when saving bezier presets in Spine.
To use this, make sure Spine is closed first (or the file may be overwritten while you edit). Find the editor-2.json file, search for curvePresets then replace the content from curvePresets:[ to the closing ] with the code below:
curvePresets:[{y1:0,y2:0,type:bezier,x1:0.12,name:easeInSine,x2:0.39},{y1:1,y2:1,type:bezier,x1:0.61,name:easeOutSine,x2:0.88},{y1:0,y2:1,type:bezier,x1:0.37,name:easeInOutSine,x2:0.63},{y1:0,y2:0,type:bezier,x1:0.11,name:easeInQuad,x2:0.5},{y1:1,y2:1,type:bezier,x1:0.5,name:easeOutQuad,x2:0.89},{y1:0,y2:1,type:bezier,x1:0.45,name:easeInOutQuad,x2:0.55},{y1:0,y2:0,type:bezier,x1:0.32,name:easeInCubic,x2:0.67},{y1:1,y2:1,type:bezier,x1:0.33,name:easeOutCubic,x2:0.68},{y1:0,y2:1,type:bezier,x1:0.65,name:easeInOutCubic,x2:0.35},{y1:0,y2:0,type:bezier,x1:0.5,name:easeInQuart,x2:0.75},{y1:1,y2:1,type:bezier,x1:0.25,name:easeOutQuart,x2:0.5},{y1:0,y2:1,type:bezier,x1:0.76,name:easeInOutQuart,x2:0.24},{y1:0,y2:0,type:bezier,x1:0.64,name:easeInQuint,x2:0.78},{y1:1,y2:1,type:bezier,x1:0.22,name:easeOutQuint,x2:0.36},{y1:0,y2:1,type:bezier,x1:0.83,name:easeInOutQuint,x2:0.17},{y1:0,y2:0,type:bezier,x1:0.7,name:easeInExpo,x2:0.84},{y1:1,y2:1,type:bezier,x1:0.16,name:easeOutExpo,x2:0.3},{y1:0,y2:1,type:bezier,x1:0.87,name:easeInOutExpo,x2:0.13},{y1:0,y2:0.45,type:bezier,x1:0.55,name:easeInCirc,x2:1},{y1:0.55,y2:1,type:bezier,x1:0,name:easeOutCirc,x2:0.45},{y1:0,y2:1,type:bezier,x1:0.85,name:easeInOutCirc,x2:0.15},{y1:0,y2:-0.56,type:bezier,x1:0.36,name:easeInBack,x2:0.66},{y1:1.56,y2:1,type:bezier,x1:0.34,name:easeOutBack,x2:0.64},{y1:-0.6,y2:1.6,type:bezier,x1:0.68,name:easeInOutBack,x2:0.32}]
Restart Spine, and you'll get all the same presets as in that page!
As an alternative, here's also a file you can open in v4.1+ that has an animation on the root with every ease above, so if you want you can select the key and manually save the preset. (the first way is much quicker though)
Download curve eases project
I hope this helps!
