In theory they would be the same, but Shogi uses the drop rule, which by its nature necessitates a way to distinguish pieces that is not dependent on color.
I did mention this as "an inconvenient necessity due to physical limitations in over-the-board play". And it is not entirely true; it is the combination of promotion and the drop rule that requires this. Otherwise you could have used different color on the backside. As this newly discovered 'South-African Chess' (Oatlali) does. (They replaced promotion by zone-dependent moving there.)
Personally I think it would have been better (in the sense that the player handling the pieces would play stronger) to flip pieces with differently colored sides on capture, and reorient them on promotion.
I did mention this as "an inconvenient necessity due to physical limitations in over-the-board play". And it is not entirely true; it is the combination of promotion and the drop rule that requires this. Otherwise you could have used different color on the backside. As this newly discovered 'South-African Chess' (Oatlali) does. (They replaced promotion by zone-dependent moving there.)
Personally I think it would have been better (in the sense that the player handling the pieces would play stronger) to flip pieces with differently colored sides on capture, and reorient them on promotion.