Norway has an abundance of hydro power. They've had an almost-entirely renewable grid even before the energy transition begin. Combine that with their small population and large oil reserves, and they have always exported far more than they have consumed domestically.

In theory the small amount of additional available oil due to domestic electrification might become available for export, but I expect that the global drop in demand due to worldwide electrification will make that unlikely: they'll just slow down production to avoid flooding the market and crashing the oil price.