Do you have any other displays which use HDMI which you can test to make sure the laptop is working Ok and your adapter & cable are fine? You can also try using a Thunderbolt 2 to VGA, DVI, or HDMI adapter to see if the issue is with the laptop's HDMI port (VGA or DVI would be best as it would eliminate HDMI issues all around if your TV supports a VGA or DVI input)?
Is your Sharp TV connected to the Internet? If so, perhaps it received a firmware update which broke something.
Or did you happen to just install a macOS update that may have broken something? You could try installing macOS 10.14 Mojave on an external USB3 drive to test the laptop as this would give you a clean OS free of any possible third party software issues and also a version of macOS without any recent patches that may have caused an HDMI compatibility issue. Testing this way also keeps you from having to wipe the internal drive for testing and later restoring from a backup. You can use the instructions in this Apple article for creating a bootable macOS 10.14 USB installer:
How to create a bootable installer for macOS - Apple Support
There is also a chance the laptop may have a GPU issue which is very common with the 2013 & earlier models, but the 2015 model may also be vulnerable although I haven't seen a lot of reports for the 2015 model.
Unrelated to your HDMI issues.....you should check to see whether your laptop qualifies for this Apple Battery Recall Program for a battery safety issue with some batteries:
15-inch MacBook Pro Battery Recall Program - Apple Support
Edit: Also do you have another computer you connect to the TV using HDMI to make sure the TV's HDMI is working properly?
