I use Visual Voicemail on AT&T in the US, but it is using the firmware provided by AT&T. Perhaps someone else can confirm whether or not it works with EE, but it is compatible as hardware is concerned.
Yes on the RM-1072 the EE firmware supports Visual Voicemail and WiFi calling. The firmware you need is RM1072_02177.00000.15221.30015_RETAIL_prod_signed_1003_026884_TMO-GB_MV.ffu