Can you please advise if, in your opinion, it is appropriate for a shaliach tzibur/chazzan to wear a tallit for the eve of rosh hashanah service?

ב"ה Shalom Yes it is most appropriate and the proper thing to do, as this has become the custom, that at ALL Tefilot on Shabbat and Festivals the shaliach tzibur wears a Tallit. The wearing of the Tallit stems from the obligation of "Cavod Hatzibur"= respect for the community and not for the obligation of Tzizit. (מגן אברהם (סי' יח סק"ב) לבוש (תקפא, א, פסקי תשובות אורח חיים סימן נג אות טו ) The earlier answer you related to is in regard to the Individual, while you refer to the Shaliach Tzibbur. All the best