It appears to redirect to en version for me pretty well. Seems pretty language agnostic, its got them all http://www.17track.net/en/track?nums=
its does track well, and I like the green how many days delivered feature.
I am finding that a lot of my orders are e-packet but tracking not working anyway so spending time to set this up feels a bit of a side project for me. It is something that could be slicker and one point where the original plugin version works better than woocommerce one. @waterlion do you need a shortcode- can't you just add the iframe in a page or does wordpress stop that? Thanks.