You stick to the wall and screw straps into the furniture on top. No one can see the straps
Remember that these are safety straps, not stability straps. They will be strong enough to prevent the bookcase from accidentally tipping over, but there will still be some jiggling which can occur. If your statues themselves are bottom-heavy and stable, then I’d say go for it!
Properly spaced, it should be adequate.
It may be necessary to use more than two straps. The fish tank must be secured to the table.
Keep it simple! Use self-threading bolts suitable for securing to metal.
No. The adhesive will not hold against the tremendous force of an earthquake or someone pulling on the cabinet. And the strap must be flat against the cabinet for the adhesive to hold. Also be sure the adhesive will stick securely to the furniture material; if adhesive won't stick, then screw the flat strap to the furniture with suitable screws.
Yes that is what I used it for.