That question won't arise, before someone (you?) starts working on ipq95xx and gets it merged and supported in OpenWrt - and only then, someone (again, you?) could start on working to support the Xiaomi 10G router. Unless you have a magic hat, maybe ask again in 4+ years (and that already assumes -which should not be taken for granted- that someone actually starts working on ipq957x pretty soon).
That aside, it is safe to assume that there will never be an opkg/ *.ipk package target for cortex a73 (not that those hypothetical packages would be binary compatible with your OEM firmware to begin with), as OpenWrt/ main has already switched to a completely different package format (apk v3) and given that the last release with opkg has already branched, without a cortex a73 target.
(just for future reference, this particular device seems to be ipq9570 (rev 001), 256NAND/ 2048).