AC Power measurement ( digital sampling)

i want to measure AC power and i want to know what is the best and safest way to digital sample AC voltage and AC current?

For AC voltage: We can use

• voltage divider and feed it to ADC with reference eg -5V to 5V ( non isolated)
• transformer to transformer from 230VAC to 5VAC and feed it to ADC (isolated)
• use voltage divider and isolation opamp or ADC ( isolated)
• are there any other options?

For AC current: We can use

• shunt resistor with opamp to adc ( non isolated and high dissipation on shunt)
• shunt resistor with isolation opamp or ADC ( same as above with isolation)
• current transformer ( can you suggest some ?) ( isolated)
• hall effect sensor ( can you suggest some?) ( isolated)
• are there any other options?

Because i need to sample the voltage and current at the same time i need two ADC, but i’m not sure what delay will be introduced for voltage ( if use any option from above) also for current ( if use any option from above) ? And if delay is introduced how can i synchronize the two ADC?

List of priorities:

1. size
2. price
3. low power ( as possible)
4. complexity

The voltage is 230Vac and max current 16A and if possible current resolution 100mA

Br.