For dictionary support have a look below.
1) Multiple dictionary lookup
Onyx, Kobo, B&N has this feature, but Pocketbook (PB) does not.
2) No dictionary file size constrain (enought for wikipedia)
PB has constains, Onyx, B&N and Kobo does not,AFAIK.
3) Collations support and care to language specific characters (while sorting)
PB supports collations, Kobo does not, but PB doesn;t sort articles in alphabet order in latin based lnaguages other that english
Morphology support (may be a stemmer)
Pocketbook has stemmer, but it is very limited in size
Onyx has this feature (stardict)
Kobo and Bookeen has support for synonyms.
This synonym approach is not suitable for agglutinative languages like Finnish, because they have more that 200 wordforms for each word, so stemmer is only solution.
5) Support for links inside dictionary
No e-ink reader has this feature except B&N
6) Support for images inside word card
No e-ink reader has this feature
7) html tags support, even more: CSS support
Maybe this can be achieved by using Webkit
No e-ink reader has this feature, except Kobo, which has basic html tag support
8) full text search support
No e-ink reader has this feature
9) support of wikipedia
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