Her tendrills tk is the best thing and you certainly aren't going to use your 100pt figure to do that. Tk, Defend and enhancement aren't great powers for a primary 100pt attacker. Even MC you typically want on lower cost figures. She's not good on this line, better on lower line.

While this feels a tad bit over costed, I could still have fun playing her. The free mind control and that tendrilkinesis are fun abilities along with the symbiotic fusion trait all the venom pieces have. Why no flight though?

This figure loses my respect because it reminds me of what we lost in Telekinesis under the 2020 rules. As is, I don't see any reason to invest 100 points in this figure for X-Men, Phoenix Force, or Venom teams. Sidestep+TK (ignoring characters!) is a great combination but to earn those points she is going to have to be damaging opponents by herself, and I don't see that being very reliable. I just don't see synergy between her defensive powers, her offensive powers, her X-Men Team Ability and her support powers. I can imagine complicated (bad) scenarios where they could gel, but I could spend the 100 points and avoid all of those scenarios.

You're looking at a 100 points of support/control. Her high cost will turn most people off, however she's capable of making cheaper figures potent. She can hide behind cheap units and grant them a high defense and bonus damage, which is harder to get these days. Being able to TK and MC from behind protection without having to worry about characters blocking her line of fire puts her in a unique position of control, with the off chance to heal whomever she TKs or get a chance at a free close attack. Don't forget she can TK herself to get those benefits as well. Needless to say free Mind Control is always nice, and can combo very nicely after TKing herself next to a target, or grant her the ability to have an approaching attacker run the other direction and possibly attack someone else.

She does get the benefit of becoming a secondary attacker if she gets pounced on, with solid powers and good attack stats.

Overall she's a finesse piece which makes her difficult to use and her high point cost makes it difficult to put her on many teams. But she's got a nice array of keywords, some of which don't have access to a lot of support powers like she has. She might also work well with pieces like Maxwell Lord if you don't care for theme.

Dag-nabbit!
when I was a kid, we didn't complain about abilities VS cost
We just Loved the sculpt,

So I will start off by saying spending 100/300 points on support is a tad difficult. However, with the TK and MC along with the improved targeting I feel this fig can be worth the cost. If you can get a few sidekicks brought in (after starting force) to guard/sacrifice the long term effects can be quite good. I'm not too sure on my favorite team to put this character with yet (w/ a 300 limit), as it does seem each team I've tried does have a fatal weakness in some area. While that is true, distracting your opponent with MC can be a pretty decent way of skirting that weakness. Overall, I'd give a 3.75/5 with most of the deficit being simply for the cost not for being a bad dial or character.

I guess symbiotes no longer hate fire??? LOL
I'm guessing the story writers created some loophole to make this character work.

Bro, explain Shriek

Yeah, that's the play here. Sidestep into TK position, TK herself next to an enemy, hope for the free attack, Mind Control as FREE on what’s left. Honestly not bad, and the Cosmic Energy TA helps.

Still, the round 100-point cost feels a tiny bit steep. The four Venom X-Men below Chase rarity add up to 310 points, played at full; if Venom Marvel Girl’s full point line were 90 points, instead, I might feel more friendly towards her.

Without, she’s just plain outclassed by Venom Magneto, even though (and, therefore) he is many times her dollar value on the aftermarket.

Can someone explain me this line?

Make a close attack targeting an opposing character adjacent to the placed character regardless of adjacency.

The wording is contradictory...

Regardless of its adjacency to Marvel Girl, MG may make a close attack on a character adjacent to an adjacent opposing character.