SetLanguage PowerPoint Add-in

PowerPoint Add-in sets appropriate language to all elements (shapes, text, boxes etc.) in PowerPoint presentation even if the default set language command doesn't do it properly

How to install PowerPoint Add-in

If you download an add-in or if a co-worker or a friend sends you the add-in, you can save it to your computer, install, and add into the available Add-Ins list.

1. Click File > Options, and then click Add-Ins.
2. In the Manage list, click PowerPoint Add-ins, and then click Go.
3. In the Add-Ins dialog box, click Add New.
4. In the Add New PowerPoint Add-In dialog box, browse for the add-in that you want to add, and then click OK.
5. A security notice appears. If you are certain that the add-in comes from a trusted source, click Enable Macros, and then click Close.

Read more at support.office.com