1. Xbox One games are pretty much the same wherever you buy/redeem from, since there are no longer region restrictions like the old days. As long as your Xbox is set to the language you want to use, it will download the local language of the game.

2. That's not accurate. I don't have any issue using my credit card to buy digital games directly from Xbox Live. I've bought using Citibank and Maybank with no issues. I can't be sure about other banks though.

3. All your purchases should carry over when you change region. I haven't tried it recently, but the last time when I changed my region from Singapore to US, all my games are still in the account. BUT, any credits you have in the account will not carry over to the new region.

Yeah, Microsoft still thinks we are not worthy of having Xbox for whatever reason. Singapore can't have THAT many Xbox users compared to Malaysia. What's wrong with at least having an official support center in Malaysia? It's such a hassle having to send my Xbox One X to Singapore the last time I had an issue.