Is your modem's LAN IP 192.168.100.1? Did you change the LAN IP of the router, 192.168.0.1? Make sure no IP conflict. Before you upgraded the firmware, did it work fine?

I think you can configure an ACL permit rule across VLANs. I only found the guidance in the UG:...

The current firmware doesn't support to block VLAN. I saw a beta firmware in another post. You can try to update the beta firmware: https://community.tp-link.com/en/business/forum/topic/266112

If you need VLAN+QoS features, I think TL-SG108E is more appropriate because it has web interface to configure these feature, but TL-SG1005D doesn't have web interface. As for the power consumption,...

What's the specific issue? Can you still access the switch's web interface? If you can't access the web interface, you can try to upgrade the firmware via the Bootutil Menu:...

Oh, I found one thing that may be helpful! Those grayed-out Wi-Fi are all working on channel 11, while the one you are able to select is on channel 1. Maybe your Fritzbox needs to work on channel1....