Most cameras today have wifi, but just to do settings and maybe DL a file now and then.
You do need capacitor camera in TX, no doubt about that, and for just sitting there when parked ( not doing parking guard ) any good camera should be able to deal with too.
But you can not do parking mode under those circumstances, if the camera was on too and generating heat too, that and the sun will push it over the thermal shut down temperature in no time.
You might be able to do parking mode if you park in the shade or in a parking garage, but out in the streets in the sun in TX,,,,,, forget about it.
Voice control i dont know why you would want, some cameras do claim like aleaxa integration, but for why i dont know, it also seem to be not working too well on the cameras that have that stuff.
In general the more "smart" stuff you want from a dashcam the more chance you have of problems, and most often it even impact image quality, so my recommendation are always go for a good "stupid" dashcam.
I cant think of any suction cup camera to recommend you, they are out there, and you can also adopt most wedge or tube shaped dashcams to some adapter suction cup mounts often used for radar detectors.