When an image is shared as Text, it is known as MMS (Short for Multimedia Messaging Service). Some operators have technological limits or countries restrict MMS. So the recipient gets a link, instead of an image.

2ndLine works on an infrastructure that is much different than a typical telephony service. Some traditional operators do not support advanced infrastructure such as 2ndLine. Hence, when you send a picture, the recipient gets a link to open the image, instead of seeing the image in Message, directly.

When the recipient taps / opens the link, s/he will see the picture you shared.