The phones that you are looking at are compatible with our GSM network which is a good start. They support LTE which is the highest level of connectivity that we are at right now using the different frequencies (band 2,4 and 12). Visual voicemail and video calling would be dependent on the software that's in the phone. There are also applications that you can download to have these features on the phone.
As for the WiFi calling, it's tough to say. The majority of phones that work are the T-Mobile branded version because they have the software built into them to connect to that aspect of the network. Universally unlocked phones like iPhone or OnePlus generally work as well since they are very open. Looking at these phones it doesn't look like they would be able to use WiFi calling out of the box. There are workarounds if you really wanted to purchase one of these phones to use on Ting that involves putting custom ROMs on to the phone. I'm not too knowledgeable about that process but find XDA Forums to be the best place to get guidence and ask questions.