Message translation is often managed with 'po' files and the 'gettext' programme, but sometimes another solution is needed. In contrast to 'po' files, a more flexible approach is used as in the Fluent < https://projectfluent.org/> project with R Markdown snippets. The key-value approach allows easier handling of the translated messages.
R packag: Simple Translation Between Different Languages
View the vignette on GitHub or after installing with
library("stranslate")
vignette("stranslate")
From CRAN
install.packages("stranslate")
From github
library("devtools")
install_github("sigbertklinke/stranslate")
Note that from github you install the current development version.