Welcome to the site !!
Not that I am aware of .... Not sure what the need for that setup would give you for just riding a 150 ..... its not like you are going really fast and need to drag your knee in the corners on it , as that is the only advantage for it , is cornering ......
What is the difficult part you are having with shifting the "normal" way ???? , just remembering what gear you are in ?? , or forgetting
and starting of in a higher gear from a light ??? .... to me it would be no different than riding my 2020 450R then getting on a old 1970 Bultaco again with the shifter on the right side and the rear brake on the left .... takes a few minutes to get used to , but after a afternoon of riding , it would seem natural . and I wouldn't give it any thought .... doing repetitive movements will train your brain to just do things without needing to think about it .... maybe that is the issue you are having , you are putting too much focus on why is is like that and getting frustrated , rather than just riding the bike and having fun ..... after a few stalls from trying to start off in 4th or 5th , or gearing down to first when trying to go faster , you will just get used to it , and you won't give it another thought ...