The ease of setup I think will also depend whether you're using On-premise Edge or Cloud Edge devices.
We are on Cloud Edges and re-used our Polycom VVX400/401 phones (ethernet via PoE) that we previously had with PureConnect.
If your phones are behind a corporate firewall and you're using Cloud Edge - there's a few rules/ports you'll need to open to make it work and can get a little complicated with all the shared AWS IP ranges still needed.
Otherwise if they are just direct internet connected, using the phones with the Polycom ZTP (Zero Touch Provisioning) service makes connecting phones anywhere a breeze.
We've also done some workarounds for the line keys (creating Speed Dials, custom soft keys, screen saver showing queues stats, etc) by activating the API within each phone, then using Power Shell to write/update parameters directly to the devices (see
https://community.polycom.com/t5/VoIP-SIP-Phones/FAQ-REST-API/td-p/98914)
The phones functionality will be relatively basic on Genesys Cloud (no Station groups, no call pickup, no shared lines/appearances, no busy-lamp indicators).
The forwarding functionality on the phone will only apply to direct user calls - if calls come via a User Group or Queue, the forwarding won't apply.
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Jeff
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