How do country indexes and ETFs (that track them) classify companies that are incorporated (or main business is in the home country) but listed elsewhere?

After much digging , i think i found the answer why MSCI China Index can have Alibaba, Tencent etc who are listed outside China but MSCI Singapore doesnt have SEA (soon to be included) , Razer .

https://www.businesstimes.com.sg/companies-mark...

Apparently MSCI has some guidelines that Singapore has not yet met under Sect 3.1.2.1 and Appendix IV of the MSCI Global Investable Market Methodology

https://www.msci.com/eqb/methodology/meth_docs/...

i think the main reason is that the size of the companies listed outside Singapore is not significant until now, with SEA and Razer and coming soon Grab.

I think indexes can be coupled with the top 500 companies or top 100 like the DJIA etc etc.

ETF however should be seen seperately as they are , by actual factrun by fund managers who are open to choose what stocks are to belong in that certain fund.

i think i might sound a little confusing here but hope that make sense.

basically and ETF and indexes / s&P 500 etc should not be linked.