Yes test is essential.

Think of what testosterone has done for you as ya a male (i assume you are a male)

Testosterone will support sexual function. and other physiological aspects.

While utilizing 19nors keep test at an HRT dose,
as will keep those physiological functions,
yet as is lower, there will be less estrogen through aromatization ,so as estrogen acts as a magnifier to prog/prolactin related sides from the tren, the lower dose will keep that to a minimum.