Based on our record, Xerces-C++ seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
A quick search turned up https://www.w3.org/wiki/XML_Schema_software - in particular https://xerces.apache.org/xerces-c/ might meet your needs. Source: over 2 years ago
pugixml - A light-weight C++ XML processing library.
Unimus - Unimus is a Network Automation and Configuration management (NCM) solution designed for fast deployment network-wide and ease of use. Unimus does not require learning any abstraction or templating languages, and does not require any coding skills.