Hi,
Z4 core is default boot core. Default multi-core project in S32DS expects this configuration.
It is possible to change this by DCF record. See SSCM_UOPS register in the reference manual.
Then there's file S32R274_UTest_Memory_Map_DCF_Rev11.xlsx attached inside the reference manual. Default_core (I can see the terms are not unified here) can be changed in dcl_soc_conf_1.
You can take a look at this application note for more details about DCF configuration (section 4):
https://www.nxp.com/docs/en/application-note/AN12553.pdf
Also this DCF configurator will be useful:
https://community.nxp.com/t5/MPC5xxx-Knowledge-Base/S32R274-DCF-Configurator/ta-p/1102353
The question is if it is worth changing it. But that's up to you.
Regards,
Lukas