Skiffle certainly kick-started the English folk revival from say 1956 onwards,because the vast majority of the revival people at that time found their way to American folk-song first while playing in skiffle groups . They(or we,to be accurate) moved from there into English folk.
   However, the skiffle groups tended to stick to American songs, so you'ld be hard put to find much English material in the repertoires of the skifflers: as people learnt English songs they forsook skiffle and started folk-groups or sang on there own. In fact,off hand I can only remember the Vipers Skiffle Group doing Maggie May as the only observable skiffle "hit" (of a minor kind) that was an English folk-song. But I expect someone will soon be by to add to the list.