Color changing or texture changing animation, object hide or disappear animation

what is the best way to change color? like green to blue smooth transition of an object. i can do it in blender, but after uploading there’s no animation at all.
also correct way of object scaling. suppose at 30th frame object is scaled 1. in 31st it is scaled 0. in blender the object is disappeared, but when uploaded on sketchfab i can see the object is getting smaller. even if the keyframe interpolation is changed. any fix for that?

Hi congestedhman, sketchfab cannot import animated textures unfortunately, but there are some tricks you could do, but they would all be quite scene specific, but in general sketchfab cannot do animated textures., Could you sort of generally describe your scene/lighting or post a pic perhaps?

Regarding the 0 scaling between 2 keyframes in blender, well it really depends what rate your playing the the animation on sketchfab, the slower the rate the more you will notice the scaling between the keyframes. But in most cases its not very noticeable , what speed are you playing the animation at? is the animation only 31 frames? or is this scaling part of a longer animation?