I looked into printing lugs a couple three years ago. Yes, you can print in wax for investment cast. A single set of lugs will be cost prohibitive compared to direct printing (at least for stainless steel). The biggest issue with direct printing is warpage. Stresses are high when you use very localized heat. I printed a prototype lug and the ID went way out of round, I believe by 0.5mm on the radius on a section of lug. The third option is 6-axis CNC. Cheaper than investment cast (for a single set of lugs), but more expensive than printing.
I'm sure things have changed in those few years in the printing world. Our lab .is looking at purchase because prices are dropping for metal printers. Warpage can be overcome with well designed supports. I'm sure I'll look into again in a year or two.
Of course all of these processes require a 3D file. I should note I am very adept using 3D CAD programs. Been using them for 25 years. They are not cheap and do take more than a weekend to learn. You can always pay someone, but it isn't inexpensive. And it is a large task to translate a lug "vision" to an actual CAD file. Communicating your design to your CAD person will not be easy. All at $125/hour.