Agree with Kingston, bar end levers solve a lot of problems when mixing road and MtB systems. This is the primary reason why bar end levers have been the common spec for so many touring bikes for so long. Then there's Gevenalle shifters https://www.gevenalle.com/shifters/

I ride with my hands on the hoods most of the time. Grew up with drop bars (and with far less friendly hood/bar shapes) and use them on all but a couple of bikes. My shifter of choice from about 1974 to 1995 was SunTour's bar ends, both the ratchet and the indexed versions. Sometimes I found trimming an inch or less from the bar's ends made reaching for the levers easier and gave me more knee clearance (not that it's a real issue). Watch your hips to hands reach growth with the switch to drop bars. Many times a shorter stem is also wanted. Andy