There are many free VSTs out there and if you want to change them with a click and run them without loading a big DAW, check out camelot. https://audiomodeling.com/camelot/overview/. Source: almost 3 years ago

Assuming you're a Windows user, there are plenty of other options. I used to use VSTHost for the same thing, but found it's a bit less stable as well as a little arcane and difficult to understand, but on the plus side it's 100% free (no paid version at all). There's also Camelot and a few others which are available for free (with limitations) but I haven't tried them all yet. And if you're on a Mac, the obvious... Source: almost 3 years ago

Another solution might be to use a plugin that can host multiple other plugins like DDMF Metaplugin or Plogue Bidule or Blue Cat's Patchwork and create your own chain with your favorite plugins. Source: 11 months ago

Check out: Vienna Ensemble Pro, pretty well known OR Metaplugin is also excellent. Source: about 1 year ago

This is what you need https://ddmf.eu/metaplugin-chainer-vst-au-rtas-aax-wrapper/. Source: over 1 year ago

Metaplugin is great, but limited for what it is (32/64 bridging + plugin chains + oversampling), and the plugin browser is a steaming pile of garbage. REAPER has functionally better routing, if less pretty, and a decent browser. Had I been on another DAW, I'd probably be interested. Source: over 1 year ago

There are plugins like metaplugin or superplugin from DDMF that allow you to load plugins (VST, VST3 & AU [AU is Mac only]) within them, but I think you will find this to be a hassle. Source: almost 2 years ago