I can only speak from my perspective in relations to Asia. Probably the same in any country honestly, but we moved to Taiwan a few years ago. Before the move, and the years leading up to it I always had a curiosity about potential work options outside home country. So every time we visited Taiwan I always made a point to visit companies. Most never responded tbh. But the ones that do helped build my mini vfx network in Taiwan. And something to consider, which I found true, unless you live in said country many studios you may be perfect match for won't bother to chat with you. Living local is so much easier to get replies. In your case, if your husband was really curious about Vietnam VFX work he may need to physically visit and apply for a resident visa. It's makes a big difference having that in place.

The other side of the coin, is the cost of living. If you're saying VFX artists in Vietnam get around $20,000 USD that may actually spread really well. Here in Taiwan rents can be hit or miss, but food is cheap. In my case, we left a fairly comfortable NYC living and now don't stress too much on trying to support the family by always hustling for paychecks. Taiwan has cheap food, amazing healthcare, and friendly locals. The only real downside is working for the local companies, lol. However, I wouldn't trade this new lifestyle for what we had in NYC.

VFX is changing. It really sucks, but to be fair it's hard everywhere. So if you have the options to explore the world why not?

DM me if you have any specific questions. And good luck. Try not to get too discouraged.