So I don't know how much you guys buy into the player trade value metrics guys like Fangraphs use, but they're a good guide imo to how teams now value prospects in trades.
It's a rough calculation but I have Stroman worth about 26.3M surplus value on the very conservative side, and 35.9M surplus value on the very optimistic end. This value is based on the 9M price of 1WAR over years of control, minus salary + projected arbitration raises.
What that means in a potential trade is, for example, is a prospect like Trevor Larnach or Brusdrar Graterol are each valued at 19M and 18M in surplus value respectively, given their years of control plus their 50FV designation.
An Update to Prospect Valuation
Putting a Dollar Value on Prospects Outside the Top 100
That means you can definitely ask for one of them + others in a trade for Stroman but probably not both (especially on the conservative end). In contrast, a guy like Kirilloff is considered to be worth 54M in surplus value, and Royce Lewis 56M which is well out of the range of what we could ask for from analytically astute teams.
A fair trade from this perspective might be something like:
Gratetol/Larnach(18/19M) + Duran/Balazovic (4M) + Smeltzer (3M) for the conservative estimate.
or
Gratetol/Larnach(18/19M) + Duran(4M) + Balazovic(4M) + Smeltzer(3M) + Wade (3M) on the high end.
Keep in mind that I picked the players I liked most at those values but there are players with similar FV values that the Twins might be more inclined to part with (for example, Jose Miranda and Yunior Severino are both 45FV and worth 4M, while Travis Blankenhorn and Cole Sands are on a long list of 40FV players worth 3M surplus value at present).
I think any return we get will probably be on the low end of this value scale.