No difference other than the wireless capabilities, also the first one includes a SIP ATA so you can connect a regular telephone to use with BSNL VOIP.
Would also need to confirm that the first device support dual mode ie both
EPON and
GPON, cause specs only mentions GPON. You cannot really generalise BSNL FTTH as the LCOs tend to use both GPON or EPON OLTs, so you might need to confirm with your operator.
Personally, I would get a basic
ONT and use it in bridge mode with a good wireless
router (
TP-Link Archer C6 is a decent device for the price)