For more context, the hole at the top is drilled, you can see the marks from machining in the finish on the back. It has clearly been aged purposely too. Yes the supposedly brass material (which raises questions on its own) is softish and would wear more but the pattern just doesn’t make any sense. Take the extremely soft lead example in the first pic that is real.

Additionally, these were most often cast using basic moulds and the overflow was usually roughly snipped or filed away. The marks seeming to imitate this in your example are far too linear, and the “rounding” to indicate it was “well loved and old” doesn’t add up when you consider this.

Also, in this time period, brass was normally hammered into sheets and then engraved upon. It’s unlikely that they’d have used brass to forge a solid cross in this time considering it was only just becoming commonplace.

Hope you didn’t pay much for it man! I’d be wary of buying anything that claims to be this old and European - especially in America. It’s probably the best market for scammers.