As title,it will be a paid option but for me it's worth it.It's still the most requested format from broadcasters and clients I have.
Good news from IBC!

link from Sony UK:CBKZ-SLMP (CBKZSLMP) : Product Overview : United Kingdom : Sony Professional (http://www.sony.co.uk/pro/product/broadcast-products-camcorders-option-boards-modules-plug-ins/cbkz-slmp/overview/#overview)

link from 4kshooters:IBC 2016: Sony PXW-FS5 Gets MPEG2 HD 422 Recording as Paid Upgrade License | 4K Shooters (http://www.4kshooters.net/2016/09/09/ibc-2016-sony-pxw-fs5-gets-mpeg2-hd-422-recording-as-paid-upgrade-license/)

Yes! I've been waiting for this. I'll be getting it.