Where can I batch “Save For Web” images before uploading?

I have 400 images ready to load to my webshop. I want to do “Save For Web”, because it should delite all metadata and xmtp headers, which ain’t usefull and makes the images heavier. Afterwards I have in mind to compress the images in XnView, because here it should be possible to batch many photos at the same time.
The problem is, that I am using Gimp, and here the “Save for web”-function doesn’t have the batch-opportunity. (In fact there schould be a way to set Gimp into batch-mode, but it seems all to nerd-difficult compared to my limited skills: https://www.gimp.org/tutorials/Basic_Batch/).

Is there a way to multi-“Save for Web” without having to invest in PS or other programs?
Or can I drop “Save for web” and reach the same effect (removed metadata and xmtp headers) in XnView or in another way?
Thank you for your help ??