"hardly overlap" is a correct and usable phrase in written English.
It means that two things or ideas have very little in common or do not coincide with each other. Example: The interests of the two brothers hardly overlap, as one is passionate about sports while the other is more interested in art and literature.
The audiences for most of these acts hardly overlap.
The issues overlap; the ideologies behind the two parties' approaches hardly overlap at all.
However much these corporate contributors may share the Tea Party minions' antipathy toward President Obama, their economic interests hardly overlap.
Skype and MySpace users hardly overlap.
Size is a fairly effective cue because large, reproductively mature benthics hardly overlap the smaller limnetics in size.
As can be seen from Figure 5, the distributions of the distances between neighbouring and distant frames hardly overlap.
Mirren says she hardly overlapped with Chastain on set, but "in a sense she created the character which I could then surf on".
Still Alice had been leaked online after Sony's server was hacked in November, but most pirate sites were swiftly shut down, and, in any case, the target audience for Still Alice hardly overlaps with regular viewers of pirated material.
The study published in CJR, on the other hand, observed that while audiences of right-wing-bubble media and the rest of the media hardly overlapped, language had a way of migrating from Breitbart into the mainstream media.
Just how long Neandertals hung on after the arrival of Homo sapiens about 45,000 years ago has been a matter of fierce debate among researchers, some of whom argue that they hardly overlapped at all.
The second interesting relationship is that the Calcium pathway hardly overlaps with the other six pathways.
