For example, just because you have a trust, with another person also a trustee, does not automatically give that person access to property that is not specifically "titled" in the name of the trust.
Well, of course not. That should be obvious.
For example, if you have a trust etc, but have a bank account in your name only, the trust/trustee would not have the authority to withdraw or obtain funds from that account, but the person holding the "power of attorney" would.
This can get dicey as well. For example, my wife had Power of Attorney, Durable Power of Attorney, Medical Power of Attorney, and Conservator/Guardianship of two elderly relatives. She was also a co-signer on their checking accounts. A very good set up, one would think. But when they died, she could NOT get immediate access to their bank accounts. Eventually, yes. Immediately, no. This is contrary to what you would expect. If the banks don't want to give you the money right away, there's not much you can do about it. You'll eventually get it, but you are at the banks whim in the short term. For her aunt, she wanted to withdraw $5000 for funeral expenses. Nope. The banks wouldn't allow it, even with all her "Powers of..." We had to pay for the funeral, and eventually got the money later. For her dad, we knew from experience, pull the funeral money out right away, immediately after his death, before the bank decided to deny it. Note that Conservator/Guardianship gives you even more power than Powers of Attorney. But that didn't help. I imagine with the large amounts of money that your representative would have to be withdrawing for your overseas plight, not just a measly $5000 for a funeral, you might be in for more banking hassle than you anticipate with your Powers of Attorney.
With our trust, we also have Powers of Attorney, Durables, Medicals, HIPPA, wills, etc. No Conservator/Guardianships though, because we are still mentally competent. These things are all necessary for good estate planning. And also a wise idea for the stuck abroad scenario.
But do they guaranty that everything will go smoothly? No, they don't. Even when you have your lawyer assist you with HIPPA forms, those don't guaranty that you can get medical information on, say, your spouse when they're in trouble. The hospital might just say "no", and that's it. They can dump new requirements on you, like "we only accept HIPPA forms if they've been completed in the last year", etc. Sure, call your lawyer and pay good money to have them pursue things for you, but by the time that's all said and done, it's already too late.
Bottom line: Do it - it can only help. But it doesn't guaranty anything.