Last 2 years Lens flare hotspot worked good for me but 1 year ago then now it doesn't work, please bring it back. I know about some software very cheaper than Panotour Pro can use lens flare and direction sound hotspot with Html5 very easy, Why can't Panotour Pro ?
Panotour Pro uses KrPano player for the virtual tours. There is no base HTML5 lens flare in the base krpano players to use, so there is no HTML5 lens flare in Panotour Pro.
Since there is a paid KrPano plugin that has HTML5 lensflares ( https://krpano.com/plugins/userplugins/lensflare/#top ), I think it is very unlikely that KrPano has any intention of adding this as a free feature to the basic KrPano players since it already "exists".
You should be able to add this krpano plugin to your tour, but it would only be from advanced editing of the built tour's code, it is not a Panotour plugin. I will not be able to help you with it's implementation since we do not provide KrPano support.