Hi, Mario, Intel discontinued development of HAXM last year because all the major operating systems include hypervisor backends of their own. As a result, QEMU removed the HAXM backend in version 8.2.
Looking at pkgsrc.se, I see that the CVS log for the emulators/haxm package mentions a quick fix to get it to build on an old version of -current, but also mentions that "this package seems to have other potential issues." I wouldn't expect it to work well with NetBSD 10. ~ James