I think Zara & Mike would be demented to get involved, and Harry and Meghan are well out of it.
On the other hand, Beatrice & Eugenie might work, if they were up for the, well, WORK part of it, and it seems less unreasonable to ask it of them than Zara!
I bet Andrew will find himself even more sacked when Charles becomes king, and if he is permanently invisible, it would only take a good PR agency a couple of years to largely rehabilitate Beatrice & Eugenie from any association with their father (or reputations of laziness), and their husbands, especially Eugenie's, might be well up for active roles (because they'd neeed to be up for it too).
Beatrice's husband Edo might be keen - he's spent his whole life actively integrating himself with the upper echelons in this country, and maybe this is what he was aiming for.
Andrew and Sarah will officially reunite now probably too, now that Philip is dead, and maybe they'll also retire to America! Charles certainly won't welcome them as a working royal couple.
I think if Andrew has done his level best to ruin their (B&E) chances of contributing to the family the way he wanted to, but it's not unsalvageable. A steady drip of positive press for a couple of years through the relevant media mouthpieces (The Times, Daily Mail etc.) would do it.
But Charles would love it to be just Kate and William, I suspect, and it's his opinion that matters.