Just a question since Adobe is ending the use of Flash. What effects does it have on my apps if I uninstall it. Poser Pro 11 uses it to manage the Runtime files and I'm worried that it won't run properly without it. I'm running MacOS Mojave (10.14.6). I also DON'T want to upgrade to Catalina due to my current Adobe software won't run and I don't have the funds at this time to upgrade them.
It's hard to say, but it sounds like it will break. You can set your date forward to something like February 2021 to check. If that's the case, you might want to think about making a virtual machine and just freezing the versions of the software that you're using, and set the date back a few years.
How do I make a Virtual Machine and freeze the software?
That's well beyond the scope of Flash Player, but to point you in the right general direction, there are some desktop virtualization solutions like VirtualBox (free), VMWare Fusion (paid), and a bunch of others, that allow you to create a virtual installation of an operating system that you then run in a window on your normal computer.
The virtualization software sits between the native operating system running on the metal of the machine and the virtual machine, abstracting away the native OS details so that future changes to the operating system don't impact the virtual machines when they run. The virtual machine just thinks it's running on normal hardware, and when things change in the ecosystem, the developer of the virtualization solution will need to update that abstraction layer to keep everything working. It's largely going to be transparent to you.
Anyway, most of those virtualization solutions let you make snapshots of the state of the virtual machine to "freeze" them in a known-good state that you can revert to.
I'm sure a quick search for "VirtualBox Tutorial install MacOS" or "VMWare Fusion Tutorial install MacOS" will get you started.
Once you have an operating system installed, you'll want to get all the stuff installed and working that you need (Poser, etc), then make a snapshot of it. You might want to set the clock back on the virtual machine a few years, too. You won't be able to surf the web like that (and you shouldn't on a machine that isn't running a fully patched browser and operating system), but it should keep everything in Poser working until you can migrate to a current version.