I installed Eudic on my e ink, but I hardly use it. Because I only connect to internet to download books or sync my reading notes to cloud, the build-in dictionary app is sufficient for me.
As pan said, Eudic would probly act slow on such a machine many years ago. In my case, it takes 2-3 seconds from long-tap the word to pop-up showing its meaning and I just mount only 1 mdx (SIO) in Eudic. (build-in app would be slightly faster, 2-3 seconds as well, but I have mounted about 30 mobi in it.)
Besides, when I want to read the dictioinary from A to Z, I prefer using my Kindle, because Android e ink would hide the dictionaries. Kindle does this job well. You can open a dictionary easily like a normal book, then you can brows and read it continuously, you even can invoke a dictionary when you’re reading a dictionary! 
OALD on my kindle, and invoke a OALD in OALD:
