I went by dealer. He said their 2019's are not that much different than a '16 and no button on LH battery box. There is one on the RH oil bag; it is the dipstick. Push to release then turn CCW to pull out . If yours is like my '06 FXDL, it doesn't leak or burn oil, anyway. Best to Know how to always check, Providence has a poor sense of humor.
A previous owner may have added a charger, cell charger, kill switch. alarm, or a tuner. Remove LH cover and see.
Most Harley owners have a little more pride, excuse my drift. When I got my FXDL I immediately read the owner's manual and checked everything. Familiarized like getting an M-16.
EDIT: Many recent Model 883 and even Model 48 Sportys have a 1200 cc engine....a 74 Cubic Inch, scotty..... A kid on a run I was on was Fast even two-up on his. I have an 88" and 660#, so he was faster than my FXDL on his lighter Sporty; almost faster than my CB650 at 440#.