whats the best way to accomplish the lowest latency possible using a Pi Zero W as a BT transmiterr

Can someone please help me find a way to use

alsa_in

and

alsa_out

to set my output to my bluetooth device

and then to set my input to my usb sound card
so i can use it with the JACK audio server?

Is there a way to turn my pi zero w into an aptX bluetooth transmitter?

https://www.newegg.com/p/1BJ-000G-000H5?item=9SIA6RP87A6552&source=region&nm_mc=knc-googlemkp-pc&cm_mmc=knc-googlemkp-pc-_-pla-alexnld-_-cables+-+3.5mm+%2f+2.5mm+stereo+cables-_-9SIA6RP87A6552&gclid=CjwKCAjwtuLrBRAlEiwAPVcZBjGFl16uSQK7wm4PEmP_45m1REPFuoUS_OdYtAZPq7h0zQZ_gN5oZxoCO3kQAvD_BwE&gclsrc=aw...

Can someone show me a way to add a line in to a pi zero??

I found this:

http://www.audioinjector.net/rpi-zero

WIll it due ?? I want to take inputted audio and transmit it via bluetooth.

if so..
can someone tell me how to connect it to a pi zero?

https://www.fdt.com.tw/product-31-2--005-06.html I found this. im trying to create a sheet music tablet with eINK display.... What does it take to get this thing to display a PDF? or some format of image on a sdcard? In addition, I need a back and forward button, plus a way to dynamically load the s...