4th Gen Looking for some johto team for my johto only challenge

[EternalSeekerX]

So I usually only play older gens ever since gen 7 dissatisfied me. So I wanted to do something different. I wanna beat heart gold to 100%, I wanna complete the story, red, e4 and end game frontier stuff with a johto only team. It should be possible? If not I'm willing to build a second team end game as well. Anyway so I just beat morty so I'm looking for some tips.

Need some resistance to fighting, ground and rock. Espeon could work?

So right now I have:

Quilava
-Focus punch (will get focus blast)
-Flamewheel (will get eruption)
-extrasensory (dont know if I will keep it)
-hidden power grass

Smeargle
-extreme speed
-judgement (I have all plates so it is any type)
-sheer cold (for the off Chance of dealing infinite damage and turning foe into nothing, one of my favorite moves)
-spacial rend (fave move)

Golbat
-x scissor
-brave bird
-feint attack (will become cross poison)
-bite

Steelix
-Toxic
-Rock Tomb (will become stone edge)
-Tackle (will become earthquake)
-Gyro ball (might replace for another steel move)

I can get a horsea soon, so

Kingdra
-Surf
-Ice beam
-Dragon pulse
-another move

So idk which johto mon to use for the last one :/ I was planning mismagius but I can't get misdrevous till mt. Silver :/