It seems some in the world want to continue the TTP agreement with Iran. However, Trump has promised sanctions against any country doing business with Iran, by way of SWIFT {I have no idea what SWIFT means] but I get the gist of what Trump would do to any country who trades with Iran. Several have stopped trade with Iran.

But: It seems that many countries want to continue trade with Iran and are searching for a means to by-pass the USA sanctions.

This has lead to talks amongst Germany, Russia and China to set up an alternative payment settlement process. Some think the pound sterling might be used or euros. Some also think the economies of Germany, China and Russia are large enough to bring other members of the EU to join an alternative payment system, and then the hope is to have Eurasia, India and others join over time. This is a huge number of potential consumers and trade volume.

I think this would be a disaster for the USD reserve status, if that many people or countries, decide they don't need the USD

Just some things that have been started in motion, with little to no success so far. [although it remains to be seen how the Chinese oil trading contracts work out]. Perhaps the rumours that the ongoing UN talks will be a minor setting to more important private discussions, that  will bring leaders from these countries together in a close setting to discuss future means to ignore the USA sanctions.

Just rumours, but it is a fact several countries want to ignore USA sanctions and if they feel the sanctions affect their domestic activity, then I would bet somebody [meaning a group of countries] will get serious about the health of their trade relationship and won't be led around by Trump.

 When so many countries, all want to continue with TTP my bet is something will eventually happen, when self interest is at stake and countries joining together in a common goal,  will give all of them the courage, to ignore USA sanctions.

I think they could do it, if they find a monetary mechanism, that would work in every bodies interest

This idea has been floating around long enough that given enough time, enough countries acting together will make it work. They know it is in their self interest to get something working, which makes people more willing to work together.

I think they will act sooner than later. When you hear about Germany giving the idea serious consideration, about joining with China and Russia, that is my signal that something will happen sooner than later..