Is there any VST plugin out there that is capable of loading other VST plugins (effects) ?
A free one, if possible :P
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Try Plogue Bidule. There is a trial of the standalone version which can really do amazing things, the paid plugin version can host other plugins.
You could write your own hosting plug-in. This paper explains the architecture:
The best plugin host I can think of would be from Steinberg themselves who were the inventors of VST:
Download this: VST 3.6.0 Audio Plug-Ins SDK
Unzip it and there will be the vst host executable in the bin folder. I test out most of the plugins I write using this. And it is quite amazing.