Two parts to consider:
1) Most software companies provide a listing of the hardware necessary to run their product. The listing is usually in the form of "minimal", "recommended", and "best".
You do not want "minimal" and you do want as much "best " as you can afford.
Trial versions may or may not be fully functional. If not fully functional then that limits thorough testing of the software and the corresponding hardware requirements.
The trial version could, for example, disable some function or feature that could bottleneck performance. And you would not discover that until the fully functional version was installed.
2) Audio and audio effects are subjective in many ways and I agree with
@dwd999 in the sense that all you can truly do is to try the software.
Especially in order to determine if the audio resulting effects,etc., do indeed meet your requirements.
For the most part you will need to try various VST applications and test them as consistently and thoroughly as you can.
Read the documentation carefully. Read the manufacturer's FAQs and Forums (if any). Pay attention to both what is said and what in not said.