The microwave slow-light delay-line has broad applications in signal processing systems,and the tunable slow-light delay-line is particularly important for adjusting the timing of wave packets and phased array beam shapers.We propose to construct multichannel microwave slow-light delay-lines using piezoelectric (PMN-PT) and piezomagnetic (CoFe2O4) superlattices(PPS).The group velocity can be slowed down by a factor of 14612 (31554) and a delay bandwidth product (DBP) of 25(47) can be achieved for the first (second) channels with a sample length of 1 cm around 10GHz (21 GHz).Furthermore,a tunable time-delay from 590ps (590ps) to 480ns (1052ns) can be realized by flipping the magnetic domains using an exteal magnetic field. The nonreciprocal polaritonic bands also contain the basic building blocks for designing the compact microwave isolator.