Can one give a glass dish with food on it to someone for mishloach manos. If so, can you toivel the dish for them? or what else should you do?
Yes, this is fine, and if used directly it should be tovelled before.
Please see sources.
There is something of a dispute concerning tevillah for utensils intended as gifts, and the Minchas Shlomo writes that it is better not to do tevillah for such utensils (because they are like utensils intended for sale and not for eating).
However, others opine that it is “simple” that tevillah can be done on behalf of the recipient (see Minchas Asher, Matos 68), though not with a berachah. It is better to make a “kinyan” on behalf of the recipient, so that the utensils will belong to him already. This should not be done for an observant Jew this should not be done, because the beracha is lost – but for somebody who might not tovel the utensils this is the best option.
In the case of Mishloach Manos, however, the person giving the Mishloach Manos is himself using the utensil to store and to present the items he wishes to give. In this case, he is using the dish “for his own use,” and can therefore do the tevillah himself.
Alternatively, the dish can be given with something separating between the dish and the food, so that there is no obligation of tevillah on the giver, and the receiver will have to tovel the utensil later.