[Question] about mirroring non-base repositories

[hagaram]

Is it possible to mirror a 3rd party repo, lets say for rabbitmq, but without selecting 'base mirror'?
The thing is I would like to mirror only few gigs instead of 100 gigs (whole distro)

I understand this is probably because of dependencies, but is there a way around it? And if.so, is it safe? I mostly lived in rpm world until now, when in comes to repos and repo mirroring.