I'll leave someone else review them and merge.
I created https://github.com/plone/Products.CMFPlone/issues/2897 as well.
I'm in vacation tomorrow until 1st July with no pc. So I'll leave it to you to do the job.
if you want to resync the plone.po files once those PR are merged:
git clone -b 5.2 email@example.com:plone/buildout.coredev.git plone52
./bootstrap.sh -c experimental/i18n.cfg
git commit "resync plone.po files"
@esteele If you need to do a new plone.app.locales release before Plone 5.2 final if you release that next week when I'm in vacation, just run git pull and fullrelease (with zest.releaser and zest.pocompile in a virtualenv) in src/plone.app.locales package like all the other packages, nothing special.