An export transaction would then be (assuming the foreign trade is transacted in foreign currency):
Domestic nongov't domestic currency account
+Xphi Domestic nongov't foreign currency account
Gov't domestic currency account
Gov't foreign currency account
Foreign domestic currency account
-Xphi Foreign foreign currency account

And since the domestic sector does not wish to hold foreign currency, it will engage in an FX transaction with the domestic CB:

An export transaction would then be (assuming the foreign trade is transacted in foreign currency):
+X Domestic nongov't domestic currency account
-Xphi Domestic nongov't foreign currency account
-X Gov't domestic currency account
+Xphi Gov't foreign currency account
Foreign domestic currency account
Foreign foreign currency account

Similarly, if the gov't wants to build strategic currency reserves, it will engage with the foreign sector:
Domestic nongov't domestic currency account
Domestic nongov't foreign currency account
-X Gov't domestic currency account
+Xphi Gov't foreign currency account
+X Foreign domestic currency account
-Xphi Foreign foreign currency account

But since the foreign sector does not wish to hold domestic currency in non-negligible amounts, it will close out its transaction by dealing with the domestic private sector:
+X Domestic nongov't domestic currency account
-Xphi Domestic nongov't foreign currency account
Gov't domestic currency account
Gov't foreign currency account
-X Foreign domestic currency account
+Xphi Foreign foreign currency account

This picture represents the net positions. You can further split each column into a full balance sheet. Which you should if you want to discuss foreign stability, because the (strong) foreign account stability condition for a non-hegemonic economy is that neg gov't long FX position exceeds the private sector's gross short FX position and that the current account is not in deficit.

- Jake

Friends come and go. Enemies accumulate.