Hey mate, thanks for your reply. been giving your question some thought and have two initial suggestions.
1. Andy Boreham, a Kiwi fluent in Mandarin who lives in Shanghai and has a YouTube channel "Reports on China". Here's a (very) short piece he did on Hong Kong's history - https://www.youtube.com/watch?v=e1uRhiY-fXM
I'm not greatly familiar with him but thought he might appeal to you as a fellow Kiwi.
2. Carl Zha, who has a podcast called "Silk and Steel" which covers Chinese history & culture and geopolitics. Carl is more the historian while Andy's more the journalist. Carl often has guests on his podcast to discuss their area of expertise and he has a continuing series of so far 10 episodes on the Opium Trade with Davide Melia, mostly behind a subscription paywall but the first episode has been unlocked here : https://www.patreon.com/posts/silk-and-steel-1-47233615
Carl has an extremely impressive follow list on X (impressive based on the stature of the ppl who follow him) and I don't know if he does many guest appearances but throwing out his name anyway.
There are others who I thought of, for example Li JingJing, but Andy might perhaps be your best bet in terms of being a smaller profile but still knowledgeable and a Kiwi to boot. Cheers