Hi Rebecca!
That is a very good question! That part of the document is known as the “MLI” (Multi-language Insert).
The first thing I will suggest is to ask the client requesting the document if they require the full MLI, or if only parts of it are required. If the recipient is known to be reader of UEB but not other braille codes, the other languages will not be useful and can be omitted without worry. This is a common outcome in my case. As you say, a transcriber’s note is included to identify this omission.
Second, if the MLI is required by your client, it will be necessary to also provide a special symbols list of the language change indicators for each of the languages to be included. I am attaching a document titled “MLI special symbols example.docx” to show you what I mean.
In that attachment, you’ll see the “dot locator for mention” and then the language change passage indicator for English (eng), Spanish (esp), and Farsi (fas). The language change passage indicator is a 3-cell symbol (highlighted in yellow in the attached document) and the language abbreviation (highlighted in green in the attached document) is inserted after the second cell of the symbol. I will recommend that you use the 3-letter language abbreviation specified in ISO 639 https://en.wikipedia.org/wiki/List_of_ISO_639_language_codes
In the same attachment I am also including several MLI paragraphs corresponding to English, Spanish, and Farsi.
The language change passage terminator is also a 3-cell symbol. I have highlighted the language change passage terminator in blue in the attached document.
There are some tools that can convert other languages to braille for those languages, but it is always necessary to spend the time proofreading. For most transcribers, producing and then proofreading of unfamiliar languages will be a symbol-by-symbol comparison using a resource like the World Braille Usage (WBU) document https://www.perkins.org/wp-content/uploads/2021/07/world-braille-usage-third-edition.pdf.
This symbol-by-symbol process is definitely time consuming — it is a “chronovore” … because it “eats time” (get it?), but very necessary no matter how the braille was actually produced.
It is relevant to note that there are occasional errors in WBU. It is also the case that some braille codes have been updated since WBU was last updated. For those reasons it will always be advisable to check with experienced transcribers and/or readers of the languages being transcribed.
If you contact me outside of Ask an Expert, I can direct you to experienced producers and proofreaders of braille in multiple languages.