When I worked for SkyTel in the nineties, I discovered that both my landline and my cellular companies could add a service called 'Fixed Call Forwarding'. This allowed calls made to either of my numbers to roll over to another pre-defined number after several rings or roll directly over to another number if my line was busy.
As they provided me with their Sky-Talk voice mail and my own toll-free access number for my voice mail service, I got the service on both lines and had them set my toll-free SkyTalk number as the number to roll over to. I was alerted on my company SkyPager when a message was left for me.
So when a voice mail was left, I was alerted on my SkyPager. I could dial my toll-free number and recover the message. Their service is still around. But they operate as 'American Messaging' now. They still sell service as SkyPager and SkyTalk.
After I left SkyTel [and no longer had their pager as my company perk], I found a company that provided dial up voice mail accounts. They gave me a local number and I had both lines changed to roll over to that number instead.
You could see if your phone providers can offer the fixed call forwarding if you can get voice mail with a separate dial up number. Perhaps they could even text your cell phone to alert you that voice mail has been received.
Not in any way that I've ever seen (not to say it can't be done, but I just haven't seen been done).
What works for me though is I ported my landline to a VOIP provider, and the home phone # will simultaneous ring on both of our cell phones. Voice-mail is usually handled in the App, or via email. Either of us sees the voice-mail is waiting, and can listen to it or see the transcription right there and then.
While I still have POTS phones plugged into a voip line adapter box, that is mostly for the kids to use it seems.