As I know,Wwise provides an IntegrationDemo with rich example code in the SDK.
It seems that the feature you want to know about happens to have a page dedicated to it.
I've taken one of the codes and put it below.
The main API for your goal is AK::SoundEngine::GetSourcePlayPosition( m_iPlayingID, &uPosition );
You can run the already compiled IntegrationDemo in the SDK and look at the code to see how to implement it.
Code Address... \Wwise2019.2.6.7381\SDK\samples\IntegrationDemo\DemoPages\...
void DemoMusicCallbacks::Draw()
{
DemoMusicCallbacksBase::Draw();
if ( m_bIsPlaying )
{
char strBuf[50];
int iPosX = m_pParentMenu->GetWidth() / 4;
int iPosY = m_pParentMenu->GetHeight() / 3;
AkTimeMs uPosition;
// Get the current play position and store it in a string buffer
AK::SoundEngine::GetSourcePlayPosition( m_iPlayingID, &uPosition );
snprintf( strBuf, 50, "Bar: %d\nBeat: %d\nPosition=%d", (int)m_uiBarCount, (int)m_uiBeatCount, (int)uPosition );
// Draw the play position and subtitles
DrawTextOnScreen( strBuf, iPosX, iPosY, DrawStyle_Text );
}
}
It was written in C++ so there should be not many difference,
Hope this helps :)