Local base means you're pandemic restriction-proof (and there might well be another one on the way)...
If working from home, I would prioritize the space: quieter neighbourhood/higher floor, good natural light and a view. If they're going to be spending most of their time at home, it had better be a space they enjoy being in. And if any demanding data needs for work, it's also worth checking on the available internet service (it can vary by building).
Really, your friend should identify their broader interests and zero in on a few neighbourhoods. Then just look for the best available flat in their budget. If easy access to Central is the goal, Southern District (Aberdeen, Ap Lei Chau) is quite nice, as it's quieter with a more open aspect/proximity to sea, while only a few MTR stops from Admiralty.
Smartone has 5G home internet, so you can use that as long as you have a good smartone signal.
Shenzhen also sounds like a good option (cheaper food options and quieter - public transport is all electric) or travel around Asia until you figure it out, does your friend want to save money or be in the heart of it all. It’s a personal preference and our suggestions mean nothing if we don’t know much about your friends lifestyle.