TesslaSE mkII is a transformer saturation simulator.
It is not a distortion box but rather focuses on bringing all those subtle saturation and widening (side-) effects from the analog right into the digital domain.
It sligthly colors the sound, polishes transients and creates depth and dimension in the stereo field. All the analog goodness in subtle doses.
It’s a mixing effect intended to be used here and there where the mix demands it. It offers a low CPU profile and (almost) zero latency.
The 2.1 update introduces VST3 support and features an improved audio transformer input stage.
https://varietyofsound.wordpress.com/2023/11/03/tesslase-mkii-update-2-1-available/