On http://i18n.mbsandbox.org/recording/*/edit_annotation, only a part of the formatting tip is translatable, the rest is always in English:

"<Translated: Annotation Formatting>

<Translated: Annotations support a limited set of wiki formatting options:>

Emphasis: ''italics''; '''bold'''; '''''bold italics'''''; ---- horizontal rule
Headings: = Title 1 =; == Title 2 ==; === Title 3 ===
Lists: tab or 4 spaces and: * bullets; 1., a., A., i., I. numbered items; spaces alone indent
Links: url; [url]; [url|label]

Because square brackets [] are used to create hyperlinks, you have to use the encoded html equivalents (&#91; for [") and (&#93; for ]) if you want them not be converted into hyperlinks. Example: If you want to use [unknown] in the annotation, you'll have to write &#91;unknown&#93; then it will appear the way you intended it to show."