Gravitational waves & cosmological redshift

Are gravitational waves streched by the expansion of the universe in the same way as EM radiation is?

In that case how does one differentiate between a gravitational wave from a given event (say neutron star merger) from one that originated from a more violent event (say black hole merger) but that has been cosmologically redshifted?

Since current black hole observation extend to about 1B light years, the red shift is not a factor. Moreover, a neutron star merger doesn't look (quantitatively) like a time dilated (medium sized) black hole merger. The former signal last on the order of 100 seconds, while that later is on the order of 200 ms. So it would take $z\approx 500$, while the most distant GRB, 090423, was at "only:" $z=8.2$.