Problem with reusing taxonomy terms with navigation settings in different term sets in Sharepoint

Suppose that we have the following sub sites in the same Sharepoint Online site collection:

• /en – publishing site
• /content/en –authoring site

And we need to use the same managed metadata navigation on these publishing and authoring sub sites. In order to achieve that we need to create 2 navigation term sets (e.g. Navigation.en-US and NavigationContent.en-US) and configure navigation settings for the terms:

We can’t use same term set for 2 sub sites because Sharepoint allows to use navigation term set for single site only. As we need to create 2 term sets anyway we would like at least to reuse terms from 1st term set Navigation.en-US in 2nd term set NavigationContent.en-US like it is shown on the picture above (in order to have less maintenance work). And here we face with the problem: it seems like that during reusing navigation settings of the terms are not reused. I.e. if we create terms in 1st term set Navigation.en-US, then reuse them in 2nd term set NavigationContent.en-US and then configure navigation settings in Navigation.en-US – reused terms in NavigationContent.en-US won’t inherit changed navigation settings automatically as we would expect.

Workaround for this problem is quite simple: at first configure navigation settings in source term set (Navigation.en-US) and only after that reuse terms in 2nd term set (NavigationContent.en-US). In this case navigation settings will be inherited properly. But if you will change navigation settings after that in original terms from the source term set – they won’t be changed automatically in 2nd term set. I.e. you will need to change them in 2nd term set explicitly.