Sorry, don't know about iEMatch, but ThomasEK answered it already. So I guess this will be your best bet.Thank you for response. Will iEMatch do the proper work in my case or can you suggest something else?
Btw, what did you mean by "I think Shure offers one"?
Edit : What do you think about this ? https://www.amazon.com/Cable-switch...00A2QJL0C/ref=cm_cr_arp_d_product_top?ie=UTF8
This product (https://www.amazon.com/dp/B00029U0X6/) offered by Shure might work without adding much resistance, but frankly I don't know for sure.
The "ER4P to ER4S" you linked will add 75 ohms resistance. That would turn your 846 into something completely different, something like a v-shaped monster.