replace shimano st-ef-41-l with shimano alivio left shift

Any Shimano front shifter of the same shift family (mtb triple) should work. At work, I have used old, parts-bin shifters as replacements on repairs due to the 2020 shortage without issue, including front shifters for old mountain or hybrid bikes, and 8-speed shifters on 7-speed drivetrains. si.shimano.com has the compatibility charts for Shimano components. the relevant part for MTB front shifter compatibility is here: https://productinfo.shimano.com/#/com/?cid=C-432&acid=C-445

if you want to confirm that the cable pull of the Acera or Alivio 3x shifter matches that of your ST-EF41, you can see that in the section "Front Drivetrain Compatibility [mtb]" ST-EF41-L appears in the box for 3x7 front shifters (SL/ST). we also see, for example, that the ST-EF505-L appears in the same box. from this we deduce that the cable pull is the same between the EF-41-L and EF-505-L.

ST-EF505-L also appears in the section for 3x9 front shifters, where it shares a box with Alivio and Acera 3x shifters such as SL-M4000-L, indicating that the 3x front shifter cable pull is shared among these systems, at least up to the level of Alivio.

You'll have to figure out what to do for a brake lever, assuming you get the standalone shifter and not an integrated unit. ST-T4000-L and ST-T3000-L are the integrated controls with mechanical brake levers and the Alivio or Acera name, although they're not the only options. often with older bikes we have simply cut the shifter portion out of the old integrated control to make room for the new shifter, rather than installing a new brake lever.

Either an Acera or Alivio 3 speed front shifter will work, in terms of having the correct cable pull. Alivio is the slightly higher-end group. if you want help choosing between the two, you can look up the shifters by part number in the specification handbook, provided you know which models you want to compare. if the Alivio option is M-4000, you'll need to go back a year or two.