[b1tman]

Yes, there is a way, I use it in my setup, but it involves a change in the setup.
First you need to move the thumbs to a network share. Assumption we use a NAS called 'NAS' and a network SMB share called 'thumbnails'
Add this to your advancedsettings.xml

Code:

<pathsubstitution>
   <substitute>
       <from>special://masterprofile/Thumbnails/</from>
       <to>smb://NAS/thumbnails/</to>
   </substitute>
</pathsubstitution>

After you restart Kodi all thumbnails will be stored in this network share. If you use the skin.helper.service from the skin all animated gifs will be stored to this share too. Now you have stored the animated gifs in a network share.

If you add your gifs manually to Kodi you need to manipulate the database. E.g Maybe you add a gif called starwars.gif to one of your movies. First store the gif in the network share \\NAS\thmubnails\gifs or whatever.
Then you can add this gif in the menu of the skin and point to the network share and to the gif at your movie. Now you have a static gif because you have stored the gif in the network share.
Now the magic part. If you look into the database and look into the entry for this gif, you see something like this: The entry points to: \\NAS\thumbnails\gifs\starwars.gif.
You need to change this entry to: special://masterprofile/Thumbnails/gifs/starwars.gif
Restart Kodi and the magic is done, you have an animated gif. I don't know why it's working, because the network share is the same but if works with this special protocol instead of SMB.

andy,
i have a cheap chinese android box, which runs kodi, download all the posters and i share it via the PNP of kodi.
how do i change the code so on my sony it would show the animated posters?