I'm still working and I have a roth-401k and a traditional-401k through my employer.
In 2018, I made an In-Service Withdrawal from my company plan to my roth-IRA and traditional-IRA that I have at a brokerage. There was no taxable event, since the money was just transferred.
Do either of these have to be reported on my taxes?
In fact, after going through all of my paperwork, I did find as dmertz noted, the 1099-R's associated with these two "distributions". They were both non-taxable events since they went from my 401k to my personal IRAs.
These distributions from traditional and Roth accounts in a 401(k) are always reportable. Your 401(k) plan is required to have provided to you by January 31, 2019 a separate Form 1099-R for each of these distributions which must be reported on your tax return.