+1 on Lee's suggestion to learn the languages. Vocabulary is not the only way in which languages communicate. I invite you to consider the English sentence "I ran over myself": you could know all the words, but unless you knew whether "myself" is being used as an adverb or as a reflexive pronoun in the objective case, you'd be very confused about the meaning! Apart from online opportunities (with which I'm not familiar), if you have a seminary or Bible college nearby, they'd probably be open to a part-time student registering just for a language class. That, of course, involves a commitment of money and scheduling that may not be workable.
As to modules, just regarding vocabulary, BDAG is superb for NT Greek, but it's often useful to see how words were used outside the biblical texts. After all, the NT writers were writing the language that everyone around them used, some at higher literary levels (Luke, Hebrews) others at lower (Mark, Revelation). Therefore getting a sense of a word's range of meanings in general Greek is also helpful. To that end, the VGNT module examines words used in the NT in light of their usage in other ancient texts, especially the numerous everyday papyrus documents that scholars had become aware of in the 19th century. It can be a little hard to follow, since it doesn't translate a lot of the Greek texts that it cites as examples, but it often raises interesting insights.
And of course when you've learned Greek and your ship comes in , you can add the LSJM module, the Greek-English dictionary that covers all of ancient Greek.