Pidgin still has a ton of modern messaging platform plugins:
OTR is sadly fairly dead; broken encryption, OTRv4 isn't out of beta yet.
Looks like OMEMO support hasn't landed either https://issues.imfreedom.org/issue/PIDGIN-16801 The Pidgin/libpurple team has a lot to handle as all of these proprietary chat options are constantly moving targets and trying to maintain feature parity on all of them. At least the FOSS options have publicly-documented specs and aren't actively hostile towards reverse engineering.
OMEMO is for XMPP only so not as useful as OTR, but there is already a plugin for it: