is there any way to change input language type using script (on ios,android,mac,pc)?

is there any way to change input language type using script (on ios,android,mac,pc)?

i have two inputfield and the one only needs to be writen in English and the other one needs to be writen in JAPANESE or something. i know it is possible manually, but i want to know how to do it automatically by scripting. i just want to change input language type into specific language when a inputfiled get focused, without real device input.