Gobo

From a networking standpoint, you can configure qos tagging for a specific application and use that dscp variable as a flag for pbr. Then set your next hop via respective tunnel.

I was looking for this

/usr/lib or /usr/lib64 or /lib (some distros) or /lib64

Some things (like hosts file) are in /etc. /etc mostly contains configs.

Have you looked into bulk rename utility?

https://www.bulkrenameutility.co.uk/