Heat always flows from an area of higher temperature to an area of lower temperature. Without specific temperature values for Block A and Block B, I cannot determine the exact direction of heat flow.
If Block A has a higher temperature than Block B, then heat will flow from Block A to Block B. Conversely, if Block B is at a higher temperature than Block A, then heat will flow from Block B to Block A.
Please provide the temperatures of each block, or if you have a diagram that indicates the temperatures, I can help analyze it further.