How was trade paid for and facilitated in the 20s and 30s?

Despite studying the history of the period in a lot of detail I have always struggled with exactly how things like trade worked. Especially with how financial controls and gold was used to stabilise currency. And how balance of trades deficits would often result in selling of foreign held assets.

If a British company imported beef from Argentina for £1m am I right in thinking that the British company pays into a British clearing account in £. And the Argentinian clearing account pays the exporter in local currency out of their own clearing account.

Then at the end of the year? The two governments tot up the balance and the nation in a trade deficit settles with a transfer of currency or gold or sells somekind of locally owned asset?
Is that how it works.

In the case of a nation like Britain, who by 1938 are getting worried about the value of the pound and exchange, might no longer want/able to settle with gold or currency and instead sell something.

Who owns the things being sold? Is this government owned assets. So British owned assets in America being sold to American government to settle? Or is it private assets being forced to sell?

Basically I'm unsure how 100 year old trade was facilitated.