  This work investigates the impacts of energy-momentum conservation violation
on the configuration of strange stars constraint with gravitational wave (GW)
event GW190814 as well as eight recent observations of compact objects. The GW
echoes from these interesting classes of compact objects are also calculated.
To describe the matter of strange stars, we have used two different equations
of state (EoSs): first an ad-hoc exotic EoS, the stiffer MIT Bag model and next
realistic CFL phase of quark matter EoS. We choose Rastall gravity as a simple
model with energy-momentum conservation violation with a set of model parameter
values. Our results show that this gravity theory permits stable solutions of
strange stars and the resulting structures can foster GW echoes. We illustrate
the implication of the gravity theory and found that the negative values of the
Rastall parameter result in more compact stellar configurations and lower GW
echo frequency. With an increase in the Rastall parameter, both the compactness
of the stellar configurations and echo time decrease. It is worth mentioning
here that with the chosen set of some probable strange star candidates from
observational data and also in light of GW 190814, we have evaluated the radii
of stellar models. Also, the GW echo frequencies associated with strange stars
are found to be in the range of {$\approx 9-27$ kHz} for both cases. {From this
work, it is also inferred that the assumption regarding the equivalence of
Rastall's theory to Einstein's theory is refuted as we have noticed many
deviations in the physical properties of the considered compact stars.
