Hello! Happy new year. We are first time home buyer closing soon on a small two-story gable house with trusses and a finished basement built in the mid-70s

We want to open up the wall (yellow) between the kitchen and living area further. The owner before last created a pass-through window and the door opening was there before.

This wall is running parallel to the shorter side of the house so I imagined it would be a straight forward partition wall. However, during the inspection we found some things puzzling and I am second guessing if it could be a load bearing wall of the weight of the second floor?

I guess once we take possession next week we could take some drywall off to check but wondering if it was common in the 70s for builders to put floor joists perpendicularly on some parts of the house?

In the basement: There is a beam running the length of the house from the front of the house until the furnace room... (red). Directly under the kitchen wall there is what appears to be maybe another beam perpendicular to the first (green). It is a finished basement so hard to tell. Peeking at the floor joists from the furnace room, it looks like floor joists from the front of the house until the end of the furnace are running width-wise. However everything past the perpendicular beam to the back of the house isn’t visible.

On the second floor above the kitchen wall, there is nothing, just the primary bedroom.

We are wondering if it’s possible that the builder made the floor joists perpendicular in the last third of the house as it is shorter in length and the roof is held up by trusses on the outer walls.

Does anyone have similar experience? Any hints on what to look for before we seek out a structural engineer?