Questions about Sony Np-Fz100

No it is not compatible, it makes you a NP-FZ50

The 7C is listed as fully compatible on the Sony website. So it should fit

Hello, No, only from A7r III, A7 III, A9, A6600

I use this Sony Battery Charger BC-QZ1

No or not directly. However, you can use the battery with the multiple battery adapter set (NPA-MQZ1K) with the A7 II (unfortunately not available at Digitec). However, you will have to decide for yourself whether this makes sense in terms of price (at least CHF 400) and connection technology (huge part). Link to the manufacturer's website: https://www.sony.ch/de/electronics/kameras-mit-wechselobjektiv-akkus-ladegeraete/npa-mqz1k

Dtc