This seems to work.
runas /trustlevel:0x20000 <program> (elevation privilege can be tested in a batch file like this)
I got the hint from runas /? where it says
/showtrustlevels displays the trust levels that can be used as arguments to /trustlevel. /trustlevel <Level> should be one of levels enumerated in /showtrustlevels. runas /showtrustlevels outputs
The following trust levels are available on your system: 0x20000 (Basic User) I haven't any deeper understanding but it seems to do the job.
Welp, turns out that this is causing issues, at least for me.
My purpose involved launching Chrome but all pages crash and fail to load.
Another issue is I can't drag-n-drop items to and from applications launched this way and the normal way.
Task Scheduler is another way. It doesn't cause above mentioned issues. Although you have to create specific tasks in advance.